Arecibo Observatory

Example dark objects in α.40

Here are six targets for the Workshop observations. These are the best of the dark galaxy candidates, as listed by Martha. They are Code 1 objects of high S/N (> 10) with nothing nearby.

ALFALFA catalog entries of the best of the dark galaxy candidates from Martha

### Formatted ALFALFA Catalog generated: Mon Jul 11 09:28:43 2011  Handchecked by Martha dropped one in VC
#Object              AGC     Other Ellipse Center  dRA dDEC Optical Center   hsize   v50 verr   W50 werr   SintP  Serr  Sintmap   SN   rms   code 
#                                  J2000                    J2000                    km/s                  Jykm/s                      mJy 
HI111126.2+052051 219215           111126.0+052044   0   0  0000 0.0+ 0 0 0    1.5 13148    2    45    4    0.96  0.04    0.88   16.6  1.90   1     1108+05d
HI113816.1+120706 215416           113816.4+120657   0   0  0000 0.0+ 0 0 0    0.5  3371    2    34    5    0.99  0.05    1.12   14.9  2.47   1     1140+13b
HI122047.0+253809 229101           122048.7+253819   0   0  0000 0.0+ 0 0 0    1.5  7116    4    43    9    0.78  0.05    0.71   13.2  1.97   1     1220+25b
HI122829.2+112458 224046           122829.4+112450   0   0  0000 0.0+ 0 0 0    1.5 16299    3   320    5    2.45  0.13    2.60   10.9  2.80   1     1228+11d
HI130336.6+074945 238802           130336.6+074938   0   0  0000 0.0+ 0 0 0    1.3  2977    2    59    4    1.24  0.05    1.04   16.7  2.13   1     1300+07b
HI143817.7+052500 249384           143817.5+052453   0   0  0000 0.0+ 0 0 0    2.3  1499    1    28    3    1.06  0.05    1.06   16.6  2.61   1     1436+05a


Optical data in vicinity of best of the dark galaxy candidates

Here are links to SDSS and DSS images and NED listings centered on the HI centroid and to the galcat screenshots showing the HI data.
Use these links to investigate the sources. Write your conclusions about each one, noting:
1. HI characteristics, e.g., what does the spectrum look like? (double-horned? Gaussian?)
2. any objects in the same field? Any spectral information for these objects contained in the SDSS that would tell you whether these galaxies are near each other in space?

219215   1111260+052044   167.8583 5.3456     Galcat Screenshot   DR7Navigate   DR8Navigate   SkyView.03   SkyView.10   DSS2red.03   DSS2blu.03   DSS2red.10   DSS2blu.10     NED1.0

215416   1138164+120657   174.5683 12.1158     Galcat Screenshot   DR7Navigate   DR8Navigate   SkyView.03   SkyView.10   DSS2red.03   DSS2blu.03   DSS2red.10   DSS2blu.10     NED1.0

229101   1220487+253819   185.2029 25.6386     Galcat Screenshot   DR7Navigate   DR8Navigate   SkyView.03   SkyView.10   DSS2red.03   DSS2blu.03   DSS2red.10   DSS2blu.10     NED1.0

224046   1228294+112450   187.1225 11.4139     Galcat Screenshot   DR7Navigate   DR8Navigate   SkyView.03   SkyView.10   DSS2red.03   DSS2blu.03   DSS2red.10   DSS2blu.10     NED1.0

238802   1303366+074938   195.9025 7.8272     Galcat Screenshot   DR7Navigate   DR8Navigate   SkyView.03   SkyView.10   DSS2red.03   DSS2blu.03   DSS2red.10   DSS2blu.10     NED1.0

249384   1438175+052453   219.5729 5.4147     Galcat Screenshot   DR7Navigate   DR8Navigate   SkyView.03   SkyView.10   DSS2red.03   DSS2blu.03   DSS2red.10   DSS2blu.10     NED1.0



Also research these objects in the Haynes 2011 α.40 catalog. Here is the link to the ALFALFA Data files page containing links to the tables in the catalog.
1. How much gas mass are these targets estimated to have?
2. Do you agree with the conclusions of the ALFALFA catalogers in terms of their surroundings? Could they have optical counterparts or be associated with debris fields?

For the proposal, write a general description of these targets. Prepare some figures showing information about the targets or a subset of the targets.

Last modified: Wed Dec 7 14:50:59 EST 2011 by martha and becky