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<!-- DOI: 10.1051/0004-6361/200911664 -->

<h2 class="sec">Online Material</h2>

<p>

<p>

<h2 class="sec"><a name="SECTION000100000000000000000"></a>
<A NAME="appendixA:sec"></A>
Appendix A: Morphology
</h2>

<p>

<h3 class="sec2"><a name="SECTION000101000000000000000"></a>
<A NAME="appendix_HH52:sec"></A>
A.1 HH&nbsp;52-53
</h3>

<p>
Our high resolution images allow us to disentangle the structure of the studied HH&nbsp;objects. Figures&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH52-3-4Hfig:fig">4</a> (right panel) and&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH52-3-fig:fig">A.1</a> show the HH&nbsp;52 and&nbsp;53 region in the three different filters. In H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">
and [S  <SMALL>II</SMALL>] HH&nbsp;52 exhibits a roughly bow shape, where knots labelled&nbsp;A can be identified as the head of the shock (nucleus). The brightest knot&nbsp;(A1) is surrounded by several smaller structures, with knots&nbsp;A3 and&nbsp;A4 placed behind, while A5 and A6 are in front, elongated towards a group of separated knots&nbsp;(D1-D3) roughly E-W&nbsp;aligned. A&nbsp;faint emission (knot&nbsp;D4) is placed just in front of the nucleus. Groups of knots B and C constitute the right and left wings of the bow, respectively. The right wing appears particularly fragmented with
knots&nbsp;B1-B3 representing a first condensation close to the nucleus. B4-B9&nbsp;are located behind.

<p>
The H<SUB>2</SUB> emission (Fig.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH52-3-fig:fig">A.1</a>, bottom) shows a more amorphous shape.
A semi-ring shaped region, roughly coincident with knots&nbsp;A2-A4, is located just behind the nucleus. Three more bright spots identify the two wings. The first emission coincides with C1 on the left wing, the second, on the right wing, extends to an area corresponding to B2 and B3 in the optical, and the third to B5 and B6 on the right wing as well. Finally, fainter and diffuse emission is detected on the D1-D3&nbsp;knots.

<p>
In addition to the three HH&nbsp;53 knots already known&nbsp;(A-C), we detect several more emissions coming from this region. Three more knots, mainly emitting in the H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">&nbsp;line (Fig.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH52-3-4Hfig:fig">4</a>), are found along the main flow, forming an elongated S-shape chain of E-W&nbsp;knots. We label C1 the emission between C and A, and B1 and B2 those close to&nbsp;B. These objects are not detected in our H<SUB>2</SUB>&nbsp;images and two of them (knots&nbsp;C1 and B1) are just barely visible on the [S  <SMALL>II</SMALL>]&nbsp;images. More diffuse emission, detected in all three filters, appears superimposed on the HH&nbsp;53&nbsp;main flow, connected to the HH&nbsp;52 streamer. HH&nbsp;53&nbsp;I lies SW, towards HH&nbsp;52, while H and E are situated NE in the opposite direction. Two brighter structures are located farther NE along the streamer. Group&nbsp;F, with a jet-like  appearance in the optical filters,
is approximately elongated towards NE, also visible in H<SUB>2</SUB>. Knot&nbsp;G, only visible in the optical, is approximatively located at the origin of the continuous emission of the streamer.

<p>
<div class="inset-old">
<table>
<tr><td><!-- init Label --><A NAME="HH52-3-fig:fig">&#160;</A><!-- end Label--><A NAME="2681"></A><A NAME="figure1440"
 HREF="img139.png"><IMG
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\par\fbox{\includegraphics[width=12.5cm,clip]{11664f16a.ps}}\\
\fbox{\includegraphics[width=12.5cm,clip]{11664f16b.ps}}\\
\end{figure}"></A><!-- HTML Figure number: 16 --></td>
<td class="img-txt"><span class="bold">Figure A.1:</span><p>
HH&nbsp;52 and HH&nbsp;53 regions with [S  <SMALL>II</SMALL>] (EMMI 2006) (<I> top</I>), and H<SUB>2</SUB> (SofI 1999) (<I> bottom</I>) filters. The labels indicate the position of the knots, including the newly detected ones. The contour levels of the [S  <SMALL>II</SMALL>] are 3, 10, 20, 30, 50, 60, 80, 90, 100, 150, 200&nbsp;<IMG
 WIDTH="13" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img3.png"
 ALT="$\times $">
<IMG
 WIDTH="12" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img4.png"
 ALT="$\sigma $">
(<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">4&nbsp;<IMG
 WIDTH="13" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img3.png"
 ALT="$\times $">
10<sup>-17</sup>&nbsp;erg&nbsp;s<sup>-1</sup>&nbsp;cm<sup>-2</sup>&nbsp;arcsec<sup>-2</sup>). H<SUB>2</SUB>&nbsp;levels are 3, 10, 20, 30, 40, 50, 60&nbsp;<IMG
 WIDTH="13" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img3.png"
 ALT="$\times $">
<IMG
 WIDTH="12" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img4.png"
 ALT="$\sigma $">
(<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">10<sup>-16</sup>&nbsp;erg&nbsp;s<sup>-1</sup>&nbsp;cm<sup>-2</sup>&nbsp;arcsec<sup>-2</sup>).</p></td>
</tr>
</table></div>
<p>

<h3 class="sec2"><a name="SECTION000102000000000000000"></a>
<A NAME="appendix_HH54:sec"></A>
A.2 HH&nbsp;54
</h3>

<p>
In Figs.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH52-3-4Hfig:fig">4</a> (left panel) and&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH54-fig:fig">A.2</a> we show the HH&nbsp;54&nbsp;images and contours in H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">,
[S  <SMALL>II</SMALL>] (left panel of Fig.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH54-fig:fig">A.2</a>) and H<SUB>2</SUB> (right panel of Fig.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH54-fig:fig">A.2</a>). The morphology of the object appears extremely complex. Our images reveal several substructures. For the sake of simplicity, we divide the description of the region in two parts, the streamer, composed of groups&nbsp;X, Y, and&nbsp;Z, and the main body of HH&nbsp;54, made up
of the remaining knots.

<p>
HH&nbsp;54 streamer shows an uncommon shape of a double helix, clearly visible in H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">.
The brightest helix is also well delineated in [S  <SMALL>II</SMALL>], appearing as a wiggling jet fragmented in
several knots. The morphology of the streamer closely resembles that of the HH&nbsp;46/47 outflow (see e.g. Eisl&#246;ffel &amp; Mundt <a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#eis94">1994b</a>; Heathcote et&nbsp;al. <A NAME="aaref38"></A><a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#heathcote">1996</a>), except for the presence of a second faint helix. The base of the streamer is X0, with knots&nbsp;X2 and&nbsp;X3 delineating the first bend of the bright helix. The path follows with X4. Y1 and&nbsp;Y2 delineate the second bend of the jet, that continues with Y4. The faint helix is delineated by X1, Y3, Y8, Y7 and Y6. Both the
bright and faint structures end in two shocks (Z and&nbsp;Z1, respectively), that barely appear as a bow shock feature in H<SUB>2</SUB> (Fig.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH54-fig:fig">A.2</a>, right panel). Molecular hydrogen emission is also detected in knots&nbsp;X0, X2, Y1, and&nbsp;Y2. A further knot&nbsp;(T) complementary to the ionic emission is
observed along the jet. Finally, some filaments&nbsp;(X4&nbsp;A, Y5, R), detected at optical wavelengths, are located aside, detached from the main flow.

<p>
The morphology of the main body appears even more complicated than the streamer. In addition to the original knots (from&nbsp;A to&nbsp;K), observed in previous papers (Schwartz <a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#schwartz">1977</a>;
Schwartz &amp; Dopita <a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#SD80">1980</a>; Sandell et&nbsp;al. <a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#sandell">1987</a>), we detect more features (labelled&nbsp;L to&nbsp;S). Moreover, several knots present sub-structures, labelled here with numbers.

<p>
Group A at the bottom appears as bow-shaped in the optical, with a&nbsp;PA of about 75
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">.
In H<SUB>2</SUB> the group exhibits emission only in the northern part of the structure, only partially overlapping the atomic emission. A&nbsp;fainter arc-shaped emission (group&nbsp;Q), mainly visible in H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">,
is located east. Knots&nbsp;P (detected in the optical) and&nbsp;S (detected in H<SUB>2</SUB>) are located west, and together with knots&nbsp;O (farther north, visible in the optical) form the farthest point of the HH&nbsp;52&nbsp;streamer.

<p>
Towards north, more groups are detected. From east to west, almost coincident in all three wavelengths, we detect groups&nbsp;K and&nbsp;E, slightly elongated northward, then group&nbsp;B, and, finally group&nbsp;F, detected only in the optical. Farther&nbsp;NE an arc-like structure is identified by groups&nbsp;J and&nbsp;M in both optical and&nbsp;NIR.

<p>
In the north-eastern region, knot I and group&nbsp;H appear as optical jets with PAs of <IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">45
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">and <IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">20
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">,
respectively. An arc emission in H<SUB>2</SUB> is delineated ahead of&nbsp;I.

<p>
In the north-western region, we detect group G, composed of five subsequent knots only detected in the optical (mainly in the H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">&nbsp;filter, see also Fig.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH52-3-4Hfig:fig">4</a>), with a&nbsp;PA of <IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">55
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">.
At&nbsp;the end of this flow another group of knots&nbsp;(C) is observed, with C1 and C2 already known, and the new knot&nbsp;C3 located on a straight line connecting knots&nbsp;G and&nbsp;C2.

<p>
It is worth to note that the identification in the NIR of knots C accomplished by Gredel (<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#gredel">1994</a>) (and then used in Caratti o Garatti et&nbsp;al. <a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#caratti06b">2006</a>; and in Giannini et&nbsp;al. <a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#giannini06">2006</a>) is erroneous. Indeed the knots that were labelled in H<SUB>2</SUB> as C1 and C2 have a similar appearance in the optical, but are situated about 6
<!-- MATH: $\hbox{$^{\prime\prime}$ }$ -->
<IMG
 WIDTH="14" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img16.png"
 ALT="$\hbox{$^{\prime\prime}$ }$">&nbsp;SW. As a consequence, the knot previously known as C1 in the NIR coincides with knot&nbsp;H2 in the optical, while C2 roughly corresponds to C1 in the optical (see Figs.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH52-3-4Hfig:fig">4</a> and&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH54-fig:fig">A.2</a>).
In this paper we use this nomenclature to avoid further confusion.

<p>
<div class="inset-old">
<table>
<tr><td><!-- init Label --><A NAME="HH54-fig:fig">&#160;</A><!-- end Label--><A NAME="2684"></A><A NAME="figure1484"
 HREF="img140.png"><IMG
 WIDTH="184" HEIGHT="133" SRC="Timg140.png"
 ALT="\begin{figure}
\par\fbox{\includegraphics[width=8.05cm,clip]{11664f17a.ps}}\fbox{\includegraphics[width=7.73cm,clip]{11664f17b.ps}}\\
\end{figure}"></A><!-- HTML Figure number: 17 --></td>
<td class="img-txt"><span class="bold">Figure A.2:</span><p>
HH&nbsp;54 regions with [S  <SMALL>II</SMALL>] (EMMI 2006) (<I> left</I>) and H<SUB>2</SUB> (SofI 1999) (<I> right</I>) filters. The labels indicate the position of the knots, including the newly detected ones. [S  <SMALL>II</SMALL>]&nbsp;contour levels are 3, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100<IMG
 WIDTH="13" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img3.png"
 ALT="$\times $">
the standard deviation to the mean background (<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">4&nbsp;<IMG
 WIDTH="13" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img3.png"
 ALT="$\times $">
10<sup>-17</sup>&nbsp;erg&nbsp;s<sup>-1</sup>&nbsp;cm<sup>-2</sup>&nbsp;arcsec<sup>-2</sup>). H<SUB>2</SUB>&nbsp;contour levels are 3, 10, 20, 30, 40, 50, 60<IMG
 WIDTH="13" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img3.png"
 ALT="$\times $">
the standard deviation to the mean background (<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">10<sup>-16</sup>&nbsp;erg&nbsp;s<sup>-1</sup>&nbsp;cm<sup>-2</sup>&nbsp;arcsec<sup>-2</sup>).</p></td>
</tr>
</table></div>
<p>

<h2 class="sec"><a name="SECTION000110000000000000000"></a>
<A NAME="appendixB:sec"></A>
Appendix B: Proper motions
</h2>

<p>

<h3 class="sec2"><a name="SECTION000111000000000000000"></a>
B.1 HH&nbsp;52-53
</h3>

<p>
Knot position angles along HH&nbsp;52 flow have a quite wide spread in their values (30
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">-80
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">). The bulk of HH&nbsp;52 and other knots, as HH&nbsp;53 C1, I, and&nbsp;H, have a PA of <IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">50
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">.
On the other hand HH&nbsp;52&nbsp;A3, A4 and a few more knots as HH&nbsp;53&nbsp;F and&nbsp;G, proceed towards HH&nbsp;54 with different PAs between 60
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">
and 80
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">.
A&nbsp;completely different behaviour is found for the features located on HH&nbsp;52 wings in the rear of the flow. Although following the bulk of the flow, they show a high degree of variability during the 20&nbsp;years of observations, as reported in Appendix&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#appendixC:sec">C</a>. Such a variability, both due to local instabilities inside the flow and fast moving shocks overtaking HH&nbsp;52 from behind, makes their identification in different epochs and a correct evaluation of the PMs and PAs sometimes difficult (see also Figs.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH52-3-pms:fig">5</a> and&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH54-pms:fig">6</a>).

<p>
In Fig.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH52-H2-pms:fig">B.1</a> H<SUB>2</SUB> proper motions are reported (see also Tables&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#PM52_h2:tab">B.3</a> and&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#PM54_h2:tab">B.4</a>). Significant measurements in HH&nbsp;52 were possible only for the three bright spots located in the wings. B2-B3 and C1 follow the flow as in the optical, with similar tangential velocities and position angles.

<p>
HH&nbsp;53&nbsp;A, B and C, in the HH&nbsp;53 outflow, exhibit small PMs with PAs around 270
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">
also in the NIR. Here, however, the measurements are less significant due to the larger errors.

<p>

<h3 class="sec2"><a name="SECTION000112000000000000000"></a>
B.2 HH&nbsp;54
</h3>

<p>
Proper motions in the HH&nbsp;54 streamer range between <IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">0.01 and 0.07
<!-- MATH: $\hbox{$^{\prime\prime}$ }$ -->
<IMG
 WIDTH="14" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img16.png"
 ALT="$\hbox{$^{\prime\prime}$ }$">&nbsp;yr<sup>-1</sup>(i.e.&nbsp;
<!-- MATH: $v_{\rm tan}$ -->
<IMG
 WIDTH="21" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img36.png"
 ALT="$v_{\rm tan}$">&nbsp;8 and 61&nbsp;km&nbsp;s<sup>-1</sup>), where the highest velocities (between <IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">30 and 60&nbsp;km&nbsp;s<sup>-1</sup>) are detected in the inner part of the flow and exhibit alternating PAs (322
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">-69
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">), likely due to precession, with directions that oscillate around an average value of&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">20
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">.

<p>
Some features, located on the edge of the streamer, are not collimated and are drifting apart (PA&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">
90
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">)
at a lower velocity. At the tip of the streamer group&nbsp;Z appears almost stationary in H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">
(
<!-- MATH: $v_{\rm tan}\sim$ -->
<IMG
 WIDTH="35" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img43.png"
 ALT="$v_{\rm tan}\sim$">
10&nbsp;km&nbsp;s<sup>-1</sup>), while in [S  <SMALL>II</SMALL>]
has a higher value of <IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">30&nbsp;km&nbsp;s<sup>-1</sup>.

<p>
Moving towards NE we observe a decrease in the tangential velocities from groups&nbsp;Q (<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">40&nbsp;km&nbsp;s<sup>-1</sup>) to K and&nbsp;E (<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">20 and 15&nbsp;km&nbsp;s<sup>-1</sup>, respectively). From the PAs and inclinations (see Sect.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#inclination:sec">4.6</a>) we can reasonably associate these knots with the HH&nbsp;54&nbsp;flow.

<p>
Group A appears as an expanding bow shock, towards ENE with an average direction of about 80
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">
and a mean&nbsp;
<!-- MATH: $v_{\rm tan}$ -->
<IMG
 WIDTH="21" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img36.png"
 ALT="$v_{\rm tan}$">
of <IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">30&nbsp;km&nbsp;s<sup>-1</sup>. Knots&nbsp;A1, A2, A6 and&nbsp;A8 exhibit some variability, as reported in Appendix&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#appendixC:sec">C</a>. Because of the morphology, the direction, and the average inclination (see Sect.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#inclination:sec">4.6</a>), the structure appears to be connected to knot&nbsp;P and to the HH&nbsp;52&nbsp;flow. Indeed part of the flow along the HH&nbsp;52&nbsp;streamer curves and shocks this region, producing group&nbsp;O as well (see also Fig.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#slit-positions:fig">1</a>). H<SUB>2</SUB>&nbsp;emission in HH&nbsp;54&nbsp;A (Fig.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH54-fig:fig">A.2</a>) appears as an expanding arc, and its motion (
<!-- MATH: $v_{\rm tan}\sim$ -->
<IMG
 WIDTH="35" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img43.png"
 ALT="$v_{\rm tan}\sim$">
30&nbsp;km&nbsp;s<sup>-1</sup>) has a different orientation depending  on the position along the structure (Fig.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH52-H2-pms:fig">B.1</a>). Proceeding from east to west, we separately measured four regions, indicated in Table&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#PM54_h2:tab">B.4</a> as A<SUB>1</SUB>, A<SUB>2</SUB>, A<SUB>3</SUB>, and&nbsp;A<SUB>4</SUB>.  The directions of the motions have different PAs with respect to the optical counterparts and it is not clear if the molecular emission comes from material swept up by the bow shock on one side (see e.g.&nbsp;HH&nbsp;219, Caratti o Garatti et&nbsp;al. <A NAME="aaref9"></A><a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#caratti04">2004</a>) or from the HH&nbsp;54&nbsp;streamer.

<p>
The faintest component of the HH&nbsp;52 streamer follows a straight trajectory (of <IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">55
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">)
and impacts ahead, producing groups HH&nbsp;54&nbsp;G and then&nbsp;C. We observe a sudden deceleration of the flow along the HH&nbsp;52&nbsp;streamer (from <IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">65 to 30&nbsp;km&nbsp;s<sup>-1</sup>) as it collides with the leading material, that is partially deflected sideways (PA&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">
80
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">). G0&nbsp;is part of such a fast flow, that shocks at the end of a slow moving component (knot&nbsp;G), changing its direction (see also Sect.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#variability:sec">4.4</a>). This dynamic is also visible in knots&nbsp;G1 and&nbsp;G3, that are not aligned with the flow, moving with a PA of <IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">80
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">
and <IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">65
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">,
respectively. Group&nbsp;C ahead of G is proceeding in the same direction at similar tangential velocities (25-30&nbsp;km&nbsp;s<sup>-1</sup>).
Surprisingly, knot&nbsp;C3, at the tip of the flow, slightly moves in the opposite direction in both optical and NIR&nbsp;filters (PA&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">
250
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">
and 
<!-- MATH: $v_{\rm tan}\sim$ -->
<IMG
 WIDTH="35" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img43.png"
 ALT="$v_{\rm tan}\sim$">
15&nbsp;km&nbsp;s<sup>-1</sup>). This behaviour is observed also in knot&nbsp;K1, on the opposite side of the HH&nbsp;object, showing nearly a reverse motion with respect to the main flows.

<p>
Velocities of knots M are quite low (about 20&nbsp;km&nbsp;s<sup>-1</sup>) with a position angle around 80
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">.
The direction and the velocities suggest that they could be part of the same outflow, generated by the same deflection mechanism.

<p>
Groups H, I and J, on the northeast side, are moving NE (PA&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">
45
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">)
with a&nbsp;
<!-- MATH: $v_{\rm tan}$ -->
<IMG
 WIDTH="21" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img36.png"
 ALT="$v_{\rm tan}$">
between 10 and 50&nbsp;km&nbsp;s<sup>-1</sup>.

<p>
Group N, in the central region of the main body, could be part of the HH&nbsp;54&nbsp;flow, with a 
<!-- MATH: $v_{\rm tan}\sim$ -->
<IMG
 WIDTH="35" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img43.png"
 ALT="$v_{\rm tan}\sim$">
20-25&nbsp;km&nbsp;s<sup>-1</sup> and a&nbsp;PA&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">&nbsp;320
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">.

<p>
It is difficult to determine the membership of several knots (as&nbsp;B or F&nbsp;groups) in the central part of the HH&nbsp;object. The bulk of knot&nbsp;B possibly moves slightly towards ESE, while&nbsp;B1, few arcseconds north, seems to proceed in the opposite direction. Also&nbsp;F and&nbsp;F1 show a similar behaviour.

<p>
The molecular component of knot B presents distinct internal motions. We detect three components, reported in Table&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#PM54_h2:tab">B.4</a> (B<SUB>1</SUB>, B<SUB>2</SUB>, B<SUB>3</SUB>, from north to south). B<SUB>1</SUB>&nbsp;appears as a bright arc in the high spatial resolution ISAAC images and it is moving towards 
NNE (<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">20
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">). B<SUB>2</SUB> and B<SUB>3</SUB> are proceeding towards ESE (130
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">-140
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">)
as in the optical. In this case we are possibly observing the motion of the two different outflows.

<p>
<A NAME="PM52:tab"></A><p class="inset-old"><a href="/articles/aa/full_html/2009/29/aa11664-09/tableB.1.html"><span class="bold">Table B.1:</span></a>&#160;&#160;
Proper Motions in HH&nbsp;52 and HH&nbsp;53 - H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">
and [S  <SMALL>II</SMALL>] - parameters derived from the linear fit.</p>
<p>
<div class="inset-old">
<table>
<tr><td><!-- init Label --><A NAME="HH52-H2-pms:fig">&#160;</A><!-- end Label--><A NAME="2689"></A><A NAME="figure1695"
 HREF="img144.png"><IMG
 WIDTH="191" HEIGHT="102" SRC="Timg144.png"
 ALT="\begin{figure}
\par\mbox{\fbox{\includegraphics[height=8.8cm,clip]{11664f18b.ps}} \fbox{\includegraphics[height=6.1cm,clip]{11664f18a.ps}} }
\end{figure}"></A><!-- HTML Figure number: 18 --></td>
<td class="img-txt"><span class="bold">Figure B.1:</span><p>
Flow charts with error bars of HH&nbsp;54 (<I> left panel</I>), HH&nbsp;52 and 53 (<I> right panel</I>) in H<SUB>2</SUB>&nbsp;filter. Proper motions and their error bars are indicated by arrows and ellipses, respectively.</p></td>
</tr>
</table></div>
<p>
<A NAME="PM54:tab"></A><p class="inset-old"><a href="/articles/aa/full_html/2009/29/aa11664-09/tableB.2.html"><span class="bold">Table B.2:</span></a>&#160;&#160;
Proper Motions in HH&nbsp;54 - H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">
and [S  <SMALL>II</SMALL>] - parameters derived from the linear fit.</p>

<p>
<A NAME="PM52_h2:tab"></A><p class="inset-old"><a href="/articles/aa/full_html/2009/29/aa11664-09/tableB.3.html"><span class="bold">Table B.3:</span></a>&#160;&#160;
Proper Motions in HH&nbsp;52 and HH&nbsp;53 - H<SUB>2</SUB>.</p>
<p>
<A NAME="PM54_h2:tab"></A><p class="inset-old"><a href="/articles/aa/full_html/2009/29/aa11664-09/tableB.4.html"><span class="bold">Table B.4:</span></a>&#160;&#160;
Proper Motions in HH&nbsp;54 - H<SUB>2</SUB>.</p>
<p>

<h2 class="sec"><a name="SECTION000120000000000000000"></a>
<A NAME="appendixC:sec"></A>
Appendix C: Flux and velocity variability
</h2>

<p>
<A NAME="acc:tab"></A><p class="inset-old"><a href="/articles/aa/full_html/2009/29/aa11664-09/tableC.1.html"><span class="bold">Table C.1:</span></a>&#160;&#160;
Accelerated Motions in HH&nbsp;52, HH&nbsp;53, and  HH&nbsp;54 - H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">,
[S  <SMALL>II</SMALL>] and H<SUB>2</SUB>&nbsp;- parameters derived from the quadratic fit.</p>
<p>

<h3 class="sec2"><a name="SECTION000121000000000000000"></a>
<A NAME="52:sec"></A>
C.1 HH&nbsp;52
</h3>

<p>
<div class="inset-old">
<table>
<tr><td><!-- init Label --><A NAME="HH52var-flux:fig">&#160;</A><!-- end Label--><A NAME="2699"></A><A NAME="figure2033"
 HREF="img147.png"><IMG
 WIDTH="204" HEIGHT="69" SRC="Timg147.png"
 ALT="\begin{figure}
\par\mbox{\includegraphics[width=9cm,clip]{11664f19a.ps} \includegraphics[width=9cm,clip]{11664f19b.ps} }
\end{figure}"></A><!-- HTML Figure number: 19 --></td>
<td class="img-txt"><span class="bold">Figure C.1:</span><p>
Variability in morphology and flux of HH&nbsp;52. <I> Left panel</I>: close up of HH&nbsp;52 from 1993 H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">
calibrated image (labels refer to 2006 image). <I> Right panel</I>: close up of HH&nbsp;52 from 2006 H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">
calibrated image. Both images have the same contour levels.</p></td>
</tr>
</table></div>
<p>

<h4 class="sec3"><a name="SECTION000121100000000000000"></a>
C.1.1 HH&nbsp;52&nbsp;B and C
</h4>

<p>
<div class="inset-old">
<table>
<tr><td><!-- init Label --><A NAME="HH52B2-flux:fig">&#160;</A><!-- end Label--><A NAME="2700"></A><A NAME="figure2042"
 HREF="img148.png"><IMG
 WIDTH="98" HEIGHT="94" SRC="Timg148.png"
 ALT="\begin{figure}
\par\includegraphics[width=8.8cm,clip]{11664f20.eps}
\end{figure}"></A><!-- HTML Figure number: 20 --></td>
<td class="img-txt"><span class="bold">Figure C.2:</span><p>
Variability in HH&nbsp;52&nbsp;B2. <I> Bottom panel</I> shows the PMs as a function of time in [S  <SMALL>II</SMALL>] (circles)and H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">
(triangles). The dashed line is the best fit to the data points. The slope of the fit gives the acceleration of the knot. In the <I> top panel</I> of the figure the measured fluxes (uncorrected for the extinction) in the two filters are reported.</p></td>
</tr>
</table></div>
<p>
<div class="inset-old">
<table>
<tr><td><!-- init Label --><A NAME="HH52C1-flux:fig">&#160;</A><!-- end Label--><A NAME="2701"></A><A NAME="figure2051"
 HREF="img149.png"><IMG
 WIDTH="98" HEIGHT="93" SRC="Timg149.png"
 ALT="\begin{figure}
\par\includegraphics[width=8.8cm,clip]{11664f21.eps}
\end{figure}"></A><!-- HTML Figure number: 21 --></td>
<td class="img-txt"><span class="bold">Figure C.3:</span><p>
Variability in HH&nbsp;52&nbsp;C1. <I> Bottom panel</I> shows the PMs as a function of time in [S  <SMALL>II</SMALL>] (circles)and H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">
(triangles). The dashed line is the best fit to the data points. The slope of the fit gives the acceleration of the knot. In the <I> top panel</I> of the figure the measured fluxes (uncorrected for the extinction) in the two filters are reported.</p></td>
</tr>
</table></div>
<p>
Both wings of HH&nbsp;52 bow-shock show a high degree of variability. As an example of such a variability, we show in Fig.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH52var-flux:fig">C.1</a> a close up of HH&nbsp;52 in 1993 and 2006 H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">
calibrated images. Changes in morphology and flux are easy to recognise, especially for the knots
of group&nbsp;B.

<p>
HH&nbsp;52 B1 and B2 come from the fragmentation of a single structure around 1987. The first knot is moving ESE with a&nbsp;PA&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">&nbsp;110
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">,
while the second is moving northward (PA&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">
5
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">). A&nbsp;third knot&nbsp;B3, clearly visible from 1989, likely causes the break, proceeding from SE to NE and pushing forward the structure. The direction of the feature considerably changes with
time in both optical filters, accordingly, from <IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">55
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">
in 1989 to 85
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">
in 1993.
Also B1 and B2 show variability (see Figs.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH52var-flux:fig">C.1</a>, <a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH52B1-fig:fig">8</a>, and&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH52B2-flux:fig">C.2</a>), exhibiting evidence of deceleration and acceleration, respectively.

<p>
Knots HH&nbsp;52&nbsp;B4-B9, in the outskirts of the wing, exhibit large variability and complicated motions as well. The presence of such a high variability and the large gap between the second to last (1993 for [S  <SMALL>II</SMALL>] and 1995 for H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">)
and the last epoch image (2006) produce uncertainties in the identification of the knots and in the PM&nbsp;derivation. A&nbsp;large structure, B5, appears in 1989 (see Fig.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH52B5-flux:fig">7</a>, top panel and also Fig.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH52var-flux:fig">C.1</a>), rapidly increasing its brightness and then almost vanishing in 2006, apparently fragmented in several knots&nbsp;(B4-B6, and&nbsp;B8), that move in different directions. The flux variation of the object has different timing in the three filters, with a delay of some years between the flux variations of [S  <SMALL>II</SMALL>] and H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">,
and then between H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">
and H<SUB>2</SUB> (Fig.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH52B5-flux:fig">7</a>, top panel).
In [S  <SMALL>II</SMALL>] it slightly varies its brightness, reaching a maximum possibly around 1991-1993. In H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">
and H<SUB>2</SUB> the variations are more considerable, especially in the molecular component, where the flux increases an order of magnitude during six years.

<p>
Knots C in the left wing of HH&nbsp;52 present a peculiar behaviour as&nbsp;well. C1&nbsp;(see Fig.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH52B5-flux:fig">7</a>, central panel and Fig.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH52C1-flux:fig">C.3</a>) shows a large variability similar to B5, with a large brightness increase in H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">,
due to the presence of a fast shock colliding against the target. This is clearly visible in 1993 and 1995 H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">&nbsp;images (Fig.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH52var-flux:fig">C.1</a>), where a high velocity knot&nbsp;(C6) appears behind&nbsp;C1. In the 2006 image the bullet is not visible anymore, but an increase in C1&nbsp;brightness is detected, in both atomic emissions. As in B5, also the molecular emission increases with time. Here the increment is not so pronounced as in the previous knot. HH&nbsp;52&nbsp;C2, located behind HH&nbsp;52&nbsp;nucleus, starts forming in 1989 as a [S  <SMALL>II</SMALL>] emission (Fig.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH52B5-flux:fig">7</a>, bottom panel) and increases its luminosity until 2006. On the other hand the H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">&nbsp;emission is visible above a&nbsp;3<IMG
 WIDTH="12" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img4.png"
 ALT="$\sigma $">&nbsp;limit only in the 2006&nbsp;image.

<p>

<h3 class="sec2"><a name="SECTION000122000000000000000"></a>
C.2 HH&nbsp;54
</h3>

<p>

<h4 class="sec3"><a name="SECTION000122100000000000000"></a>
<A NAME="streamer54:sec"></A>
C.2.1 HH&nbsp;54 streamer
</h4>

<p>
<div class="inset-old">
<table>
<tr><td><!-- init Label --><A NAME="HH52Y2-flux:fig">&#160;</A><!-- end Label--><A NAME="2702"></A><A NAME="figure2082"
 HREF="img150.png"><IMG
 WIDTH="101" HEIGHT="97" SRC="Timg150.png"
 ALT="\begin{figure}
\par\includegraphics[width=9cm,clip]{11664f22.eps}
\end{figure}"></A><!-- HTML Figure number: 22 --></td>
<td class="img-txt"><span class="bold">Figure C.4:</span><p>
Variability in HH&nbsp;54&nbsp;Y2. <I> Bottom panel</I> shows the PMs as a function of time in [S  <SMALL>II</SMALL>] (circles), H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">
(triangles), and H<SUB>2</SUB> (squares). The dashed line is the best fit to the data points.  The slope of the fit gives the acceleration of the knot.
In the <I> top panel</I> of the figure the measured fluxes (uncorrected for the extinction) in the three filters are reported.</p></td>
</tr>
</table></div>
<p>
Figure&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH52Y2-flux:fig">C.4</a> (bottom panel) displays the peculiar kinematics of HH&nbsp;54&nbsp;Y2, located in the middle of the streamer. The proper motion measurements reveal an apparent acceleration of the knot, detected in all three filters. However, due to the faint emission, errors in H<SUB>2</SUB> appear remarkably larger. Here, the PM&nbsp;measurements are referred to epoch 2002, since in H<SUB>2</SUB> 2005 image Y2 is out of the FoV. We measure an acceleration of 0.006&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
0.0002
<!-- MATH: $\hbox{$^{\prime\prime}$ }$ -->
<IMG
 WIDTH="14" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img16.png"
 ALT="$\hbox{$^{\prime\prime}$ }$">&nbsp;yr<sup>-2</sup> and  0.01&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
0.004
<!-- MATH: $\hbox{$^{\prime\prime}$ }$ -->
<IMG
 WIDTH="14" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img16.png"
 ALT="$\hbox{$^{\prime\prime}$ }$">&nbsp;yr<sup>-2</sup> in H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">
and H<SUB>2</SUB>, respectively (see Table&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#acc:tab">C.1</a>). The average value obtained including both optical (H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">
and [S  <SMALL>II</SMALL>]) and molecular PMs is 0.0031&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
0.0008
<!-- MATH: $\hbox{$^{\prime\prime}$ }$ -->
<IMG
 WIDTH="14" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img16.png"
 ALT="$\hbox{$^{\prime\prime}$ }$">&nbsp;yr<sup>-2</sup>. Thus a mechanism must exist there that is accelerating the streamer or, conversely, the observed motion could be a reminiscence of the original acceleration experienced by the flow. The upper panel of Fig.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH52Y2-flux:fig">C.4</a> reports the measured flux for the three filters. For this object, all the emissions appear almost constant with time (inside the error bars). This is indeed due to the high degree of ionisation along the HH&nbsp;54&nbsp;streamer.

<p>
Also along the streamer it is possible to observe the formation of new condensations. A&nbsp;new H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">&nbsp;knot is forming <IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">1
<!-- MATH: $.\!\!^{\prime\prime}$ -->
<IMG
 WIDTH="9" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img22.png"
 ALT="$.\!\!^{\prime\prime}$">6&nbsp;ENE of HH&nbsp;54&nbsp;Y3. This is probably an instability in the flow created by the material compressed and pushed ahead of&nbsp;Y3.

<p>

<h4 class="sec3"><a name="SECTION000122200000000000000"></a>
<A NAME="54A:sec"></A>
C.2.2 HH&nbsp;54&nbsp;A
</h4>

<p>
Figure&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH54A-flux:fig">C.5</a> illustrates flux variability in HH&nbsp;54&nbsp;A group. Here, at variance with other knots, the measured velocities are constant (inside the error bars) in all the three filters.
The brightest feature (knot&nbsp;A1, bottom panel) doubles its H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">
luminosity, after 1990. Variability is, however, not observed in [S  <SMALL>II</SMALL>], which appears constant during the considered period. The molecular emission, that does not spatially coincide with the atomic one but it is located about 1
<!-- MATH: $.\!\!^{\prime\prime}$ -->
<IMG
 WIDTH="9" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img22.png"
 ALT="$.\!\!^{\prime\prime}$">6 forward, from 1993 shows an increase with time. Knot&nbsp;A8, next to A1 along the flow, appears in H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">&nbsp;images in 1989 (Fig.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH54A-flux:fig">C.5</a>, top panel), and increases its brightness in all the three filters, and it is extremely luminous in the molecular component. In both [S  <SMALL>II</SMALL>] and H<SUB>2</SUB> it has a diffuse emission, probably originating from moving gas cooling behind the H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">&nbsp;emission. The feature has a different direction (PA&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">
35
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">)
with respect to the bulk of the flow (PA&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">
80
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">). This deflection could be generated in the interaction with knot&nbsp;A6 (see also Fig.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH54-fig:fig">A.2</a>), a faint emission following the group, that seems to push aside&nbsp;A8, or, conversely, it could indicate that the knot is not part of the same&nbsp;flow.

<p>
<div class="inset-old">
<table>
<tr><td><!-- init Label --><A NAME="HH54A-flux:fig">&#160;</A><!-- end Label--><A NAME="2703"></A><A NAME="figure2108"
 HREF="img151.png"><IMG
 WIDTH="101" HEIGHT="100" SRC="Timg151.png"
 ALT="\begin{figure}
\par\includegraphics[width=9cm,clip]{11664f23.eps}
\end{figure}"></A><!-- HTML Figure number: 23 --></td>
<td class="img-txt"><span class="bold">Figure C.5:</span><p>
Measured fluxes (uncorrected for the extinction) in knots HH&nbsp;54&nbsp;A1 (<I> bottom panel</I>), and A8 (<I> top panel</I>) in [S  <SMALL>II</SMALL>] (circles), H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">
(triangles), and H<SUB>2</SUB> (squares) filters.</p></td>
</tr>
</table></div>
<p>

<h4 class="sec3"><a name="SECTION000122300000000000000"></a>
<A NAME="54G:sec"></A>
C.2.3 HH&nbsp;54&nbsp;G
</h4>

<p>
A few arcseconds ahead of knots G and G0 (see Sect.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#variability:sec">4.4</a>), also knots
HH&nbsp;54 G1 and G3 are deflected (PA&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">
60-80
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">)
and accelerated (see Figs.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH54G1-flux:fig">C.6</a>,&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH54G3-flux:fig">C.7</a>), likely by the same mechanism of HH&nbsp;54&nbsp;G/G0.

<p>
<div class="inset-old">
<table>
<tr><td><!-- init Label --><A NAME="HH54G1-flux:fig">&#160;</A><!-- end Label--><A NAME="2704"></A><A NAME="figure2122"
 HREF="img152.png"><IMG
 WIDTH="101" HEIGHT="97" SRC="Timg152.png"
 ALT="\begin{figure}
\par\includegraphics[width=9cm,clip]{11664f24.eps}
\end{figure}"></A><!-- HTML Figure number: 24 --></td>
<td class="img-txt"><span class="bold">Figure C.6:</span><p>
Variability in HH&nbsp;54&nbsp;G1. <I> Bottom panel</I> shows the PMs as a function of time in [S  <SMALL>II</SMALL>] (circles) and H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">
(triangles).  The dashed line is the best fit to the data points. The slope of the fit gives the acceleration of the knot. In the <I> top panel</I> of the figure the measured fluxes (uncorrected for the extinction) in the two filters are reported.</p></td>
</tr>
</table></div>
<p>
<div class="inset-old">
<table>
<tr><td><!-- init Label --><A NAME="HH54G3-flux:fig">&#160;</A><!-- end Label--><A NAME="2705"></A><A NAME="figure2131"
 HREF="img153.png"><IMG
 WIDTH="101" HEIGHT="96" SRC="Timg153.png"
 ALT="\begin{figure}
\par\includegraphics[width=9cm,clip]{11664f25.eps}
\end{figure}"></A><!-- HTML Figure number: 25 --></td>
<td class="img-txt"><span class="bold">Figure C.7:</span><p>
Variability in HH&nbsp;54&nbsp;G3. <I> Bottom panel</I> shows the PMs as a function of time in [S  <SMALL>II</SMALL>] (circles) and H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">
(triangles). The dashed line is the best fit to the data points. The slope of the fit gives the acceleration of the knot. In the <I> top panel</I> of the figure the measured fluxes (uncorrected for the extinction) in the two filters are reported.</p></td>
</tr>
</table></div>
<p>

<h4 class="sec3"><a name="SECTION000122400000000000000"></a>
<A NAME="54H:sec"></A>
C.2.4 HH&nbsp;54&nbsp;H 
</h4>

<p>
<div class="inset-old">
<table>
<tr><td><!-- init Label --><A NAME="HH54H:fig">&#160;</A><!-- end Label--><A NAME="2706"></A><A NAME="figure2142"
 HREF="img154.png"><IMG
 WIDTH="101" HEIGHT="200" SRC="Timg154.png"
 ALT="\begin{figure}
\par\includegraphics[width=9cm,clip]{11664f26a.eps}\vspace*{5mm}
\includegraphics[width=9cm,clip]{11664f26b.eps}
\end{figure}"></A><!-- HTML Figure number: 26 --></td>
<td class="img-txt"><span class="bold">Figure C.8:</span><p>
Variability in HH&nbsp;54&nbsp;H1 <I> upper Figure</I> and H2 <I> bottom Figure</I> The <I> bottom panels</I> show the PMs as a function of time in both [S  <SMALL>II</SMALL>] (circles) and H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">
(triangles). The continuous and dashed lines in the top figure are the best fits of the data points with and without 1993 data points (see text), respectively. The slope of the fits gives the deceleration of the knot. In the <I> top panel</I> of the figures the measured fluxes (uncorrected for the extinction) in the two filters are reported.</p></td>
</tr>
</table></div>
<p>
Group HH&nbsp;54&nbsp;H is a very active and fast variable region of the&nbsp;flow.

<p>
Between 1987 and 1993 H1 has decreased the speed in the optical bands from 40 to 20&nbsp;km&nbsp;s<sup>-1</sup>with a&nbsp;PM&nbsp;deceleration of 0.02&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
0.01
<!-- MATH: $\hbox{$^{\prime\prime}$ }$ -->
<IMG
 WIDTH="14" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img16.png"
 ALT="$\hbox{$^{\prime\prime}$ }$">&nbsp;yr<sup>-2</sup> in H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">
(see Table&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#acc:tab">C.1</a>), and a value of 0.0025&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
0.0012
<!-- MATH: $\hbox{$^{\prime\prime}$ }$ -->
<IMG
 WIDTH="14" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img16.png"
 ALT="$\hbox{$^{\prime\prime}$ }$">&nbsp;yr<sup>-2</sup>, or 0.0063&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
0.0005
<!-- MATH: $\hbox{$^{\prime\prime}$ }$ -->
<IMG
 WIDTH="14" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img16.png"
 ALT="$\hbox{$^{\prime\prime}$ }$">&nbsp;yr<sup>-2</sup> without considering 1993 data, combining all the optical PMs (see upper Fig.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH54H:fig">C.8</a>, bottom panel). During this period the H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">
and [S  <SMALL>II</SMALL>]&nbsp;fluxes gradually increase from 4.9&nbsp;<IMG
 WIDTH="13" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img3.png"
 ALT="$\times $">
10<sup>-15</sup>&nbsp;erg&nbsp;s<sup>-1</sup>&nbsp;cm<sup>-2</sup> to 7.2&nbsp;<IMG
 WIDTH="13" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img3.png"
 ALT="$\times $">
10<sup>-15</sup>&nbsp;erg&nbsp;s<sup>-1</sup>&nbsp;cm<sup>-2</sup>, and 1.8&nbsp;<IMG
 WIDTH="13" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img3.png"
 ALT="$\times $">
10<sup>-15</sup>&nbsp;erg&nbsp;s<sup>-1</sup>&nbsp;cm<sup>-2</sup> to 2.8&nbsp;<IMG
 WIDTH="13" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img3.png"
 ALT="$\times $">
10<sup>-15</sup>&nbsp;erg&nbsp;s<sup>-1</sup>&nbsp;cm<sup>-2</sup>, respectively (top panel).

<p>
Knot H2 (see lower Fig.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH54H:fig">C.8</a>, bottom panel) apparently drops in velocity between 1987 and 1989 H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">,
changing the PM&nbsp;value  from <IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">0.08 to 0.04
<!-- MATH: $\hbox{$^{\prime\prime}$ }$ -->
<IMG
 WIDTH="14" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img16.png"
 ALT="$\hbox{$^{\prime\prime}$ }$">&nbsp;yr<sup>-1</sup> (decelerating of 0.022&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
0.002
<!-- MATH: $\hbox{$^{\prime\prime}$ }$ -->
<IMG
 WIDTH="14" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img16.png"
 ALT="$\hbox{$^{\prime\prime}$ }$">&nbsp;yr<sup>-2</sup> in H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">,
see Table&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#acc:tab">C.1</a>). The knot has also a relevant flux variability at least in the H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">
and H<SUB>2</SUB>&nbsp;emissions, that have a constant increase of the flux from 2.7&nbsp;<IMG
 WIDTH="13" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img3.png"
 ALT="$\times $">
10<sup>-15</sup>&nbsp;erg&nbsp;s<sup>-1</sup>&nbsp;cm<sup>-2</sup> (1987) to 8.5&nbsp;<IMG
 WIDTH="13" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img3.png"
 ALT="$\times $">
10<sup>-15</sup>&nbsp;erg&nbsp;s<sup>-1</sup>&nbsp;cm<sup>-2</sup> (2006) in H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">,
and from 7.6&nbsp;<IMG
 WIDTH="13" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img3.png"
 ALT="$\times $">
10<sup>-15</sup>&nbsp;erg&nbsp;s<sup>-1</sup>&nbsp;cm<sup>-2</sup> (1993) to 16&nbsp;<IMG
 WIDTH="13" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img3.png"
 ALT="$\times $">
10<sup>-15</sup>&nbsp;erg&nbsp;s<sup>-1</sup>&nbsp;cm<sup>-2</sup> (2005) in&nbsp;H<SUB>2</SUB>. On the other hand the measured flux in the three [S  <SMALL>II</SMALL>]&nbsp;images is&nbsp;constant.

<p>
Finally H3 emission appears only in 2006 optical images, whereas in H<SUB>2</SUB> it appears as a faint featureless emission and no significant motion is detectable. Again, the gap between the second to last and the last optical images makes it hard to derive the initial position of the condensation. We have tried to correlate it with a feature close to H2 in 1993, but the interpretation is not certain.

<p>

<h2 class="sec"><a name="SECTION000130000000000000000"></a>
<A NAME="appendixD:sec"></A>
Appendix D: Radial velocity
</h2>

<p>

<h3 class="sec2"><a name="SECTION000131000000000000000"></a>
D.1 HH&nbsp;52 flow 
</h3>

<p>
Along the HH&nbsp;52 flow, knots have radial velocities from about -70 to -90&nbsp;km&nbsp;s<sup>-1</sup>, with lower values detected at the end of the flow, in&nbsp;HH&nbsp;54, where the velocity decreases moving from&nbsp;G to&nbsp;C, indicating that the flow has been decelerated. The lowest value is detected in HH&nbsp;54&nbsp;C2 (-18&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
4&nbsp;km&nbsp;s<sup>-1</sup>) at the very end of the flow. C3&nbsp;is following C2 at a higher
velocity (-45&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
4&nbsp;km&nbsp;s<sup>-1</sup>) (see Table&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH54vrad1:tab">D.3</a>). Along the jet, in knots&nbsp;G1-G3, we observe two distinct velocity  components of -87 and -21&nbsp;km&nbsp;s<sup>-1</sup>. In the EMMI&nbsp;spectral image the emissions are well separated, delineating two distinct lines of similar 
intensities for each detected species (see Table&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH54vrad1:tab">D.3</a>). At the base of the jet, where G0 and&nbsp;G are located, the fast component, extending a few arcseconds from the HH&nbsp;52&nbsp;streamer to&nbsp;G0, shows an abrupt deceleration (from -78 to -18&nbsp;km&nbsp;s<sup>-1</sup>) and then ahead, along the flow, 
a second slower velocity component is detected. Also in consideration of the proper motion analysis, where a portion of the flow appears to be deflected in this region, the two velocities could be ascribed to the two flow components, rather than a bow shock structure. Moreover, due to the profile of the observed emission lines, a hypothetical bow shock would lie close the plane of the sky
(see e.g. Hartigan et&nbsp;al. <a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#hart87">1987</a>), but, as the inclination angle suggests (see also Sect.&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#inclination:sec">4.6</a>), this is not the&nbsp;case.

<p>
Two velocities components, not completely separated, are also detected in HH&nbsp;52 knots located in front (D4) and behind (A3-A4) the nucleus&nbsp;(A1, 
<!-- MATH: $v_{\rm rad}$ -->
<IMG
 WIDTH="22" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img45.png"
 ALT="$v_{\rm rad}$">&nbsp;= -79&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
6&nbsp;km&nbsp;s<sup>-1</sup>) (see Table&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH52vrad1:tab">D.1</a>). Velocities in A3-A4 are slightly higher (-98&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
5&nbsp;km&nbsp;s<sup>-1</sup> and -35&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
6&nbsp;km&nbsp;s<sup>-1</sup>), with respect to&nbsp;D4 (-85&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
3&nbsp;km&nbsp;s<sup>-1</sup> and -30&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
3&nbsp;km&nbsp;s<sup>-1</sup>). Line fluxes of the low velocity component are considerably fainter
than the other component. The velocity profiles of the H<IMG
 WIDTH="11" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img2.png"
 ALT="$\alpha $">&nbsp;line in both structures closely match the theoretical profile of a bow shock with an inclination angle of <IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">60
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">
with respect to the plane of the sky (see Hartigan et&nbsp;al. <a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#hart87">1987</a>) and a shock velocity of 70-80&nbsp;km&nbsp;s<sup>-1</sup> (observed from the <I>full width zero intensity&nbsp;- FWZI</I>, measured on the 
spectrum where the flux reaches a&nbsp;2<IMG
 WIDTH="12" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img4.png"
 ALT="$\sigma $">&nbsp;background noise level, see e.g. Davis et&nbsp;al. <a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#davis01">2001</a>).

<p>

<h3 class="sec2"><a name="SECTION000132000000000000000"></a>
D.2 HH&nbsp;53 flow 
</h3>

<p>
The highest 
<!-- MATH: $v_{\rm rad}$ -->
<IMG
 WIDTH="22" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img45.png"
 ALT="$v_{\rm rad}$">
values are observed in the three knots of HH&nbsp;53 (see Table&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH53vrad1:tab">D.2</a>) outflow, A&nbsp;(-110&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
10&nbsp;km&nbsp;s<sup>-1</sup>), B&nbsp;(-113&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
9&nbsp;km&nbsp;s<sup>-1</sup>), and C&nbsp;(-96&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
14&nbsp;km&nbsp;s<sup>-1</sup>), derived averaging the radial velocities of the different species from B&amp;C&nbsp;slit&nbsp;1 and&nbsp;2. In the EMMI spectrum (Table&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH53vrad1:tab">D.2</a>) it is not possible to spatially disentangle the emission coming from knots&nbsp;C and&nbsp;C1. Here, however, we measure two different velocities of -104&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
7&nbsp;km&nbsp;s<sup>-1</sup> and -55&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
18&nbsp;km&nbsp;s<sup>-1</sup>. Considering that the two knots are from two separate flows, the higher velocity should be ascribed to knot&nbsp;C and the lower to&nbsp;C1.

<p>

<h3 class="sec2"><a name="SECTION000133000000000000000"></a>
D.3 HH&nbsp;54 flow 
</h3>

<p>
Along the portion of the HH&nbsp;54 streamer encompassed by our B&amp;C&nbsp;slits, we measure an increase in the velocity moving towards the main body of HH&nbsp;54 (see also Table&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH54vrad1:tab">D.3</a>). The values rise from about -50&nbsp;km&nbsp;s<sup>-1</sup>, roughly at the base of the streamer&nbsp;(X1A-X3), up to -100&nbsp;km&nbsp;s<sup>-1</sup>, close to the middle&nbsp;(X4A-X4B). Such a behaviour was also observed by
Graham &amp; Hartigan (<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#GH88">1988</a>), but the value measured in the middle (considering also the errors) is lower than ours of <IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">10-20&nbsp;km&nbsp;s<sup>-1</sup>. Such a difference in their values could be due to a not perfect positioning of the slit, due to the sinuous geometry of the HH&nbsp;54&nbsp;streamer.

<p>
<A NAME="HH52vrad1:tab"></A><p class="inset-old"><a href="/articles/aa/full_html/2009/29/aa11664-09/tableD.1.html"><span class="bold">Table D.1:</span></a>&#160;&#160;
Radial velocities and line intensities for different optical lines of individual knots in HH&nbsp;52 from EMMI and B&amp;C&nbsp;spectra. Radial velocities are corrected for the cloud speed with respect to the&nbsp;LSR (
<!-- MATH: $v_{\rm LSR}$ -->
<IMG
 WIDTH="27" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img8.png"
 ALT="$v_{\rm LSR}$">&nbsp;= 2&nbsp;km&nbsp;s<sup>-1</sup>, Knee <a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#knee">1992</a>). When detected, two velocity components are reported.</p>
<p>
<A NAME="HH53vrad1:tab"></A><p class="inset-old"><a href="/articles/aa/full_html/2009/29/aa11664-09/tableD.2.html"><span class="bold">Table D.2:</span></a>&#160;&#160;
Radial velocities and line intensities for different optical lines of individual knots in HH&nbsp;53 from EMMI and B&amp;C&nbsp;spectra. Radial velocities are corrected for the cloud speed with respect to the LSR (
<!-- MATH: $v_{\rm LSR}$ -->
<IMG
 WIDTH="27" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img8.png"
 ALT="$v_{\rm LSR}$">&nbsp;= 2&nbsp;km&nbsp;s<sup>-1</sup>, Knee <a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#knee">1992</a>). When detected, two
velocity components are reported.</p>
<p>
<A NAME="HH54vrad1:tab"></A><p class="inset-old"><a href="/articles/aa/full_html/2009/29/aa11664-09/tableD.3.html"><span class="bold">Table D.3:</span></a>&#160;&#160;
Radial velocities and line intensities for different optical lines of individual knots in HH&nbsp;54 from EMMI and B&amp;C&nbsp;spectra. Radial velocities are corrected for the cloud speed with respect to the LSR (
<!-- MATH: $v_{\rm LSR}$ -->
<IMG
 WIDTH="27" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img8.png"
 ALT="$v_{\rm LSR}$">&nbsp;= 2&nbsp;km&nbsp;s<sup>-1</sup>, Knee <a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#knee">1992</a>). When detected, two
velocity components are reported.</p>
<p>
<A NAME="FeIIvrad:tab"></A><p class="inset-old"><a href="/articles/aa/full_html/2009/29/aa11664-09/tableD.4.html"><span class="bold">Table D.4:</span></a>&#160;&#160;
[Fe  <SMALL>II</SMALL>] radial velocities of the individual knots of HH&nbsp;54
obtained from ISAAC high resolution spectroscopy, corrected for the cloud speed with respect to
the LSR (
<!-- MATH: $v_{\rm LSR}$ -->
<IMG
 WIDTH="27" HEIGHT="26" ALIGN="MIDDLE" BORDER="0"
 SRC="img8.png"
 ALT="$v_{\rm LSR}$">&nbsp;= 2&nbsp;km&nbsp;s<sup>-1</sup>, Knee <a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#knee">1992</a>). When detected, two velocities components are reported.</p>
<p>

<h2 class="sec"><a name="SECTION000140000000000000000"></a>
<A NAME="appendixE:sec"></A>
Appendix E: Inclination and spatial velocity
</h2>

<p>
In HH&nbsp;52 bow shock we obtain an average inclination with respect to the sky plane of 58
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
3
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">,
excluding D2-D3 measurement, that shows a value of 67
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
4
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">.
HH&nbsp;53&nbsp;E1 and&nbsp;F2, as already deduced from the PM analysis, are part of the same outflow with inclinations of 57
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
3
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">
and 63
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
4
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">,
respectively.
The association of groups HH&nbsp;54&nbsp;G and&nbsp;C to the HH&nbsp;52&nbsp;outflow is also confirmed. HH&nbsp;54&nbsp;G0 has an inclination of 55
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
3
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">,
at the end of the streamer. Moreover, if we assume that along HH&nbsp;54&nbsp;G1-G3 the high and low radial velocities are associated with the high and low tangential velocities observed along the jet, we obtain inclinations ranging between 50
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
4
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">
and 56
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
5
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">,
respectively. Values in HH&nbsp;54 C2 and&nbsp;C3 are 61
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
3
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">
and 52
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
8
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">,
respectively. Spatial velocity along the flow are around 100&nbsp;km&nbsp;s<sup>-1</sup> (see Table&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#incl:tab">E.1</a>) and decreases in group&nbsp;G and&nbsp;C (20-50&nbsp;km&nbsp;s<sup>-1</sup>).

<p>
HH&nbsp;53 A, B, and C have similar inclinations (83
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
2
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">)
and spatial velocities (around 110&nbsp;km&nbsp;s<sup>-1</sup>). HH&nbsp;53&nbsp;C1 is superimposed on the second flow and is moving accordingly with the HH&nbsp;52&nbsp;streamer, with an inclination angle of <IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img5.png"
 ALT="$\sim $">49
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
9
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">,considering the low velocity component measured in HH&nbsp;53&nbsp;C-C1 spectrum (see Table&nbsp;<a href="/articles/aa/full_html/2009/29/aa11664-09/aa11664-09.html#HH53vrad1:tab">D.2</a>).

<p>
In the HH&nbsp;54 streamer we measure an average inclination angle of 67&nbsp;<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img9.png"
 ALT="$\pm$">
3
<!-- MATH: $\hbox{$^\circ$ }$ -->
<IMG
 WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
 SRC="img15.png"
 ALT="$\hbox{$^\circ$ }$">,
but the errors of the single data points are too large to derive variations of inclination along the wiggling jet.

<p>
<A NAME="incl:tab"></A><p class="inset-old"><a href="/articles/aa/full_html/2009/29/aa11664-09/tableE.1.html"><span class="bold">Table E.1:</span></a>&#160;&#160;
Inclination and spatial velocities of individual knots of HH&nbsp;52, 53, and&nbsp;54 inferred from the kinematical analysis.</p>
<p>

<p>
<br>

</div></body></html>