Volume 539, March 2012
|Number of page(s)||49|
|Published online||05 March 2012|
VVDS020106882 This galaxy has a regular velocity field. The velocity dispersion is higher on the southeast side but remains low. Some external pixels are detected on the northwest side. They seem to be related to regions associated to the galaxy due to concordant velocities. Two objects (including a very faint one) are detected in I-band at less than 6′′ but are not detected in the SINFONI datacube. VVDS020116027 This galaxy has a small companion at 4′′ to the north. The companion is detected in Hα but with a low S/N and over a region of the size of the seeing. This companion is less exposed than the main galaxy. The main galaxy itself seems to have two components in the Hα flux distribution and has a very low velocity shear. VVDS020147106 Despite a low-velocity gradient and some perturbations in the low S/N regions, the kinematic position angle of this galaxy agrees well with the I-band morphology. This galaxy may therefore be a nearly face-on disk (at least the ionized gas) but with a high velocity dispersion. There are several objects detected in I-band but not in the SINFONI datacube at less than 6′′. VVDS020149061 The I-band image suggests small and extremely faint companions that are not detected in the SINFONI datacube, however . The seeing is half the size of the Hα emission. The velocity field is irregular on the edges where the S/N is lower and the velocity dispersion is higher than 70 km s-1 everywhere in the galaxy (except at the edges). VVDS020164388 Except for the edge, the velocity field and the velocity dispersion map are regular. Velocity dispersion is not higher than 60 km s-1. In the I-band image, the galaxy is quite round. Several faint close objects are also observed in this image but are not detected in Hα. VVDS020167131 Some [Oiii] is detected in the center but there are only a few pixels and the S/N is lower than 4. In addition, some emission line is detected at the same redshift in the center of the galaxy on the east seen in the I-band. This indicates that these two galaxy are in interaction. VVDS020182331 The velocity gradient is clear even if we exclude low S/N regions (bluest and reddest velocities). However, the velocity field and velocity dispersion map look perturbed, probably because of the low S/N of the observation. A very close companion is detected in the I-band image that is undetected in Hα. VVDS020193070 Despite a generally low S/N, the velocity field is quite regular except in the outskirts. The velocity dispersion is low but slightly asymmetric. The morphology is elongated both in I-band and in Hα (but with a difference of ~10° between morphological and kinematic major axis position angles). Three very faint objects are detected at less than 5′′ from the galaxy but are not detected in Hα. VVDS020208482 The S/N is fairly low but there is a clear velocity shear. The I-band image shows a close galaxy and other objects, farther away, that are not detected in Hα. VVDS020214655 This galaxy displays a fairly smooth low velocity gradient, but not aligned with the morphology, which is quite round. There are some perturbations in the low S/N regions of the velocity field. There are also small perturbations in the velocity dispersion map, which is fairly flat and has low values. There is a close galaxy in the I-band (at ~2′′) that is not detected in Hα. VVDS020239133 The morphology from I-band is clearly elongated and is more extended than that in Hα. The velocity field is asymmetric but shows a clear gradient. The velocity dispersion map is also perturbed and has a high-velocity dispersion in the south that could be explained by a sky line residual. Two objects are observed in I-band but not detected in Hα within the SINFONI field-of-view. VVDS020240675 The velocity field is perturbed, with a low-velocity gradient. The velocity dispersion is fairly low (~40 km s-1). In addition, the size of the Hα emission is not large compared to the seeing. There is some emission detected at 2′′ in the east of the main galaxy, but nothing is detected in the I-band at this location. There are also several objects in I-band within 6′′ that are not detected in Hα. VVDS020255799 The signal in Hα for this galaxy is not extended and with a mean S/N lower than 5. There is no clear regular velocity gradient. One object is detected at 5′′ in I-band but not in Hα. VVDS020261328 The velocity field is not completely regular in the blue and red sides. There is also a peak in the velocity dispersion where the S/N is lower. Several objects are detected in I-band but not in Hα. VVDS020278667 Some Hα is detected, but the extent is lower than the seeing, and the S/N is lower than 5. Therefore its classification is very doubtful. There is a close galaxy (~1.5′′) in the I-band but it is not detected in Hα. VVDS020283083 This galaxy looks asymmetric in the I-band and this coincides with the Hα distribution and with the main perturbation of the velocity field. This could be related to a tidal tail. That is why this galaxy is classified as non-isolated. VVDS020283830 In the Hα flux map there is a faint detection smaller than the seeing that coincides with a detection in the I-band (north-east). For the main object, the distribution is asymmetric. This is also true in the Hα distribution, which is clumpy. These clumps may be either star-forming regions in one single rotating galaxy or two small objects in the process of merging. VVDS020294045 The total velocity shear is larger than 50 km s-1. However, both the I-band and the Hα images are consistent with a system involving two components: one main component with a low-velocity gradient (south) and one small component with a size comparable to the seeing (north). This interpretation is supported by the high-velocity dispersion between the two components due to beam smearing between the two components at different radial velocities. There is a sky line residual at the velocity of the small component, but the flux detected is noticeable. It is therefore not possible to classify the small component. This system is classified as interacting with a flag B since it could also be a single object but with strong perturbations. VVDS020363717 The I-band shows a close (~1′′), very diffuse and faint object that is not detected in the Hα (southwest). The velocity shear is low. The velocity field is perturbed in the low S/N regions. The velocity dispersion map is also perturbed and the velocity dispersion is high (~90 km s-1) after beam smearing correction.
VVDS020370467 Both velocity field and velocity dispersion map are perturbed. The velocity gradient of the model is low and the velocity dispersion is quite high (higher than 70 km s-1) in particular at the north edge (higher than 150 km s-1). This could be a sign for a strong interaction due to merging, but there is also a sky line residual that could induce the line width. In addition some objects are observed in the I-band image at less than 6′′ but are not detected in Hα. VVDS020386743 The Hα distribution is very elongated for this galaxy, but no velocity gradient is visible. Both velocity field and velocity dispersion are smooth. The I-band image shows a distorted galaxy compatible with the Hα distribution. In the north, the distortion is compatible with a faint detection in Hα that could be related to a minor close companion. VVDS020461235 The velocity field of this galaxy is perturbed. There is a blob detected in Hα in the southwest side. This blob is also suggested in the I-band morphology but is less clear. This blob has velocities compatible with the rotation of the main component but could as well be a minor companion in the process of merging. This system is therefore classified as interacting with a flag B. VVDS020461893 The velocity field is regular but the velocity dispersion is less regular and high and could suggest a high-dispersion clump. An object is observed at 3′′ southward in the I-band image but is not detected in SINFONI data. VVDS020465775 Both velocity field and velocity dispersion map are irregular. The gradient of the model is lower than 50 km s-1. We claim that there is a companion in the northwest that induces broad and non-Gaussian (hence a lower S/N) lines interpreted as a sign of interaction that could also be responsible for the asymmetry in the I-band. Hence it is classified as interacting with a flag B since it could also be a single object but with strong perturbations. VVDS140083410 The velocity field is perturbed and there is no clear overall velocity gradient. No galaxy is detected at less than 8′′ in the I-band image. VVDS140096645 The velocity field is smooth but with some perturbations along the minor kinematic axis. The velocity dispersion map is perturbed and larger on the southern side probably due partially to a sky line residual. Some emission is detected in the Hα map outside the main component (north). This detection is smaller than the seeing and is not clearly confirmed in the I-band morphology (CFHT12k images are less deep than CFHTLS images). It could be a minor companion but it is also compatible with the velocity of the main component and could be associated to it. Therefore it is classified as interacting with a flag B. This galaxy also has an AGN (see Queyrel et al. 2012). VVDS140123568 Some Hα is detected, but there are only a few pixels and the S/N is lower than 4. Therefore its classification is very doubtful. There is no detected object in the I-band image at less than 6′′ around the galaxy. Since the kinematics does not allow to investigate a possible ongoing merger, the isolation has a flag B. VVDS140137235 Some Hα is detected, but there are only a few pixels and the S/N is lower than 4. Therefore its classification is very doubtful. There is no detected object in the I-band image at less than 6′′ around the galaxy. Since the kinematics does not allow to investigate a possible ongoing merger, the isolation has a flag B. VVDS140217425 The velocity field is regular and has the highest shear (~600 km s-1). The velocity dispersion map shows two regions with high-velocity dispersions (>150 km s-1). These regions are associated with a lower S/N. This is because there are double profiles in these regions that induce a poor fit. These double profiles are caused by the beam-smearing that mixes regions with different velocities. This can be interpreted as the presence of star-forming clumps at the edge of the galaxy and a large clump in the center. The decomposition of the profile using two Gaussian scales down the velocity dispersion to usual values, and shows that the two external clumps have no velocity gradient, whereas the central one does have one. This picture is compatible with a rotating disk in which the rotational velocity reaches a plateau before the external clumps. Using the double profile decomposition instead of the kinematics model to derive the maximum velocity, we find Vmax ~ 312 ± ~20 km s-1, which is much more realistic than the value found from the model. The velocities of the plateau are ~+313 and ~−312, which shows that the rotation curve is fairly symmetric and therefore favors a rotating disk hypothesis. Correcting for the inclination, we obtain Vmax = 322 km s-1. However, the I-band image is asymmetric (which is not incompatible with the previous statement), and it cannot be ruled out that the external clumps are instead objects about to merge with the main component. VVDS140258511 The velocity field and velocity dispersion map look perturbed at the northeast edge but this may be due to a sky line residual. Except at this location, the velocity dispersion is low (less than 40 km s-1). VVDS140262766 The velocity field and the velocity dispersion map are not strongly perturbed and the velocity dispersion is about 50 km s-1. Several objects are seen at less than 5′′ in the I-band image but are not detected in Hα. VVDS140545062 This object has a clear and smooth velocity shear compatible with the I-band and Hα morphology. However, the velocity field is not very well reproduced by the rotating disk model: one side is faster than the other. The velocity dispersion map shows a peak in the southwest side. This peak is caused by a double profile that may be interpreted as a sign of merging (late stage or ongoing merger). However, since the system as a whole is isolated (no galaxy at less than 7′′ in I-band), this galaxy was classified as isolated with a flag B. VVDS220014252 Both velocity field and velocity dispersion map are perturbed. In addition, the morphology in I-band is asymmetric. This system has a high-velocity dispersion (>80 km s-1) and is peaked on some edges. This may be a sign of merging (ongoing or remnant). However, the system is isolated and there is no other evidence for some companion except one very faint object in I-band at ~5′′, which is not in the SINFONI field-of-view. So this system is classified as isolated. VVDS220015726 The velocity field of this galaxy is well reproduced by a rotating disk model. The velocity dispersion map is peaked in the center, which agrees with the expected effect of beam smearing caused by the inner velocity gradient. The velocity field and velocity dispersion map are slightly perturbed. One very faint component is detected in I-band at around 4′′ but is not detected in Hα. VVDS220148046 This galaxy has been observed using AO and is therefore less deep than seeing-limited observations. Some emission line was detected but with a low S/N (~4). It appears that the redshift determined from the VVDS was wrong and that we observed [Oiii] at z = 2.2442. The emission is compact and therefore it is not possible to conclude about the kinematics. VVDS220376206 A small component (smaller than the seeing, hence a flag B for the environment classification) is detected in Hα and is confirmed in the I-band image (north). The residual velocity field shows signs of interaction. The main component has two blobs in Hα and the I-band morphology is slightly asymmetric. The velocity dispersion map is also perturbed and peaked on the edges. This may be a sign of interaction or of the end of a merging event. VVDS220386469 This observation was made with AO and is underexposed (owing to the small pixel size, cf. Contini et al. 2012). Even if the AO observation does not allow a fair comparison with other galaxies in the same conditions because of the smaller field of view, this system is classified as isolated with a flag B since the closest clear detection in the I-band image is farther than the 6′′ that would be reached using the seeing-limited observing strategy. The velocity field is irregular and the velocity dispersion is very small but this may be due to the use of AO, which provides more details and a lower S/N than seeing-limited observations. The extent of the velocity field is small so it is difficult to argue that there is no velocity gradient at all in this galaxy. VVDS220397579 This system is the clearest interacting system between two large galaxies. The two objects are detected in Hα and in the I-band. Both are elongated toward the same direction. The main object in Hα and in I-band has a smooth velocity field with no gradient except on the northern side, near the companion. This region coincides with a higher velocity dispersion and this is probably related to the interaction with the companion. Since the galaxies are aligned and since the overall velocity gradient is monotonic, the whole system might be considered as a unique galaxy with two big clumps. However, such a system would be very much extended, a property which is physically unlikely at these redshifts. The companion shows a clear velocity shear and has been classified as well. It is also worth noticing that the minor companion in I-band is the most luminous in the K-band (from UKIDSS Deep Extragalactic Survey, Lawrence et al. 2007), therefore likely the most massive one. VVDS220544103 This galaxy has a clear velocity gradient. The object is distorted in the I-band image as well as in Hα. This can be explained by the presence of two components (the morphology was decomposed using this hypothesis). In that case, the southern component may be well described by a rotating galaxy and the brightest blob in Hα (north) maybe a companion in a merging stage or a relic of merging. However, it cannot be ruled out that this is a single object with disturbed morphology and kinematics, hence the flag B. VVDS220544394 The Hα map clearly shows the presence of a main component and a faintest one in the north. Their velocity fields seem decorrelated enough to claim that these are two separated objects on a pre-merging stage. The small component is also clearly detected in the I-band. The velocity field of the main component is perturbed but shows a velocity shear. Its velocity dispersion is about 50 km s-1. The small component is slightly larger than the seeing and may also be considered to have a velocity shear. VVDS220576226 The velocity field is perturbed in the north where the S/N is the lowest. The velocity dispersion map is regular. Two objects are observed within 6′′ in the I-band image but are not detected in Hα.
VVDS220578040 The I-band image shows an asymmetric galaxy with a more diffuse emission in the east. The Hα map shows two blobs. These can be interpreted either as two distinct galaxies or as two clumps in one single galaxy. The velocity field is perturbed and is not fully reproduced by the model. The velocity dispersion map is slightly perturbed. Since no strong kinematics perturbation is observed, this galaxy is classified as isolated (with a flag C) and therefore its kinematics is interpreted as a sign of rotation. VVDS220584167 The I-band morphology is distorted and the Hα distribution is asymmetric. The kinematic position angle, however, agrees very well with the morphology. The velocity field shows some perturbations such as a slight asymmetry. This could be due to the position of the kinematic center that would differ from the morphological one. The velocity dispersion map is peaked in the center, however, but the beam smearing may not account for the whole amplitude of the peak. Two objects are detected in I-band but not in Hα at less than 6′′. VVDS220596913 This galaxy is a chain galaxy in the I-band. It has been observed both with and without AO (cf. Contini et al. 2012). Several blobs are detected in Hα. They can be interpreted as several clumps in a single edge-on galaxy since the velocity field is monotonic. They can also be interpreted as several small galaxies in a merging stage. The continuum was extracted from the SINFONI data around Hα and seems to be peaked in the center, between the Hα blobs, which favors the edge-on hypothesis. Since no strong kinematics perturbation is observed, and since a previous seeing-limited observation (Epinat et al. 2009) revealed that no extra emission is detected, this galaxy is classified as isolated with a flag B and therefore its kinematics is interpreted as sign of rotation. VVDS910193711 This observation was made with AO. The extent is larger than 1′′. The velocity field is perturbed. The interpretation of the perturbations may not be comparable with seeing-limited observations because the S/N is lower and the scale of the perturbations smaller. The velocity dispersion is high (around 100 km s-1). In the close neighborhood that would be observed using the seeing-limited strategy, several objects are detected in the I-band image. VVDS910279515 This galaxy was observed using AO and is therefore less deep than seeing-limited observations. This galaxy is unclassified since there are only a few pixels with a S/N larger than 3. There are several objects in the I-band image at less than 5′′ that would have been observed using a seeing-limited strategy.
This appendix shows the kinematic maps for all detected galaxies. There are several sets of maps for galaxies with detected companions: one for the whole system (without kinematics modeling) and one for each modeled component.
Maps for VVDS020106882. From left to right: (top) the I-band CFHT image (arbitrary scale), the Hα flux map (arbitrary scale) and the S/N map, (middle) the observed velocity field, the rotating-disk-modeled velocity field, the residual velocity field, the uncertainty map on the velocity field, (bottom) the observed uncorrected velocity dispersion, the velocity dispersion map deduced from the velocity field model (beam-smearing effect and spectral PSF), the beam-smearing-corrected velocity dispersion map and the uncertainty on the velocity dispersion. The redshift is indicated in the top-left. In each map, north is up and east is left. The center used for kinematics modeling is indicated as a double black and white cross, the position angle is indicated by the black line. This line ends at the effective radius. The seeing FWHM is indicated on the Hα map as a circle.
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Maps for VVDS020116027 system. From left to right: (top) the I-band CFHT image (arbitrary scale), the Hα flux map (arbitrary scale) and the S/N map, (middle) the observed velocity field, the uncertainty map on the velocity field, (bottom) the observed uncorrected velocity dispersion and the uncertainty on the velocity dispersion. The redshift is indicated in the top-left. In each map, north is up and east is left. The seeing FWHM is indicated on the Hα map as a circle.
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© ESO, 2012
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