From the 2MASS Public Outreach and Education Page
Analysis by Photometry:
There hasn't been very much official photometry
done on either of the objects that make up Arp 273 and so there is not
much information about the relative luminosities at various
wavelengths.
There is a Spectral Energy Distribution for UGC01810 but there are only 7 photometric datapoints and only from the B band in the visual part of the spectrum and the HI (aka. 21 cm line) and so more work would have to be done before this distribution could really be compared with any others.
The magnitudes measured for the B band and HI line are as follows:
| Passband | Associated Frequency | Measurement | Units | Reference |
| B (m_B) | 6.81E+14 Hz | 13.42 +/-0.19 | mag | 1 | B (m_B^0) | 6.81E+14 Hz | 12.92 | mag | 2 |
| HI (21 cm line) | 1.42E+09 Hz | 14.67 +/_ 0.10 | m_21 mag | 3 |
| HI (21 cm line) | 1.42E+09 Hz | 15.62 | Jy*km/sec | 4 |
| HI (21 cm line) | 1.42E+09 Hz | 16.03 | Jy*km/sec | 5 |
| HI (21 cm line) | 1.42E+09 Hz | 15.61 | Jy*km/sec | 6 |
| HI (21 cm line) | 1.42E+09 Hz | 12.22 | Jy*km/sec | 7 |
In researching the Current Knowledge of this galaxy pair I came across two photomerty papers which included Arp 273. one measured the magnitude through a red filter (6500 Angstroms). UGC01810 was found to have a magnitude of 12.5 and UGC01813 was found to have a magnitude of 13.6 (both have an associated error of 0.2-0.3 mag). (Reshetnickov, V.P., Hagen-Thorn, V.A., Yakovleva, V.A. Astronomy and Astrophysics, Suppl. 99, 257-289, 1992). The other imaged and did photometry on the pair through B,V,R and I filters. The magnitudes were as follows:
| UGC01810 | B | 13.69+/-0.22 |
| V | 12.63+/-0.06 | |
| R | 12.28+/-0.05 | |
| I | 11.99+/-0.07 | |
| UGC01813 | B | 15.34+/-0.17 |
| V | 14.07+/-0.06 | |
| R | 13.60+/-0.05 | |
| I | 13.18+/-0.07 |
Laurikainen, E., Salo, H. Astronomy and Astrophysics Suppliment Series, 141, 103-111 (2000)
A Qualitative Visual Analysis:
There may not be many measurements at different wavelengths but thanks to
Skyview (NASA's virtual
observatory) we can get images of Arp 273 from surveys done at different
wavelenths and do a visual comparison.
***For information on any of the surveys from Skyview visit the Survey Information Page***
The overlayed numbers are from the Updated Zwicky Catalogue. UGC01810 and UGC01813 (the two galaxies that make up Arp 273) are numbers one and two and their information from the catalogue is as follows:
Number Catalog Cat ID RA(2000) DEC(2000)
-----------------------------------------------------------------
1 uzc UZC J022132.7+3 02 21 32.65 +39 21 23.8
2 uzc UZC J022128.6+3 02 21 28.56 +39 22 31.0
[The Updated Zwicky catalog (UZC). Falco E.E., Kurtz M.J., Geller
M.J.,
Huchra J.P., Peters J., Berlind P., Mink D.J., Tokarz S.P., Elwell B.
Publ. Astron. Soc. Pac. 111, 438 (1999)]
From the
2MASS Public Outreach and Education Page
Gamma-Rays:
Surveys done with Gamma-Rays are usually looking for active galaxtic nucleai caused by super-massive black holes or gamma ray bursts whose cause has not yet been determined. (Gamma-Ray Large Array Space Telescope Student Page)
We can see that surveys done in this wavelenth range don't have good
enough resolution to show much (both objects plus a lot of the surounding
area all fall within one of the smallest divisions of detection) and so
were probably done to find areas to
look at in more detail. We can
tell however that the area which includes Arp 273 doesn't seem to be much
different from the surrounding area and consequently there are likely
no super-massive black holes present or gamma-ray bursts around the
time of the survey.
Egret > 100 Mev 
Energy=30-100 MeV |
Egret < 100 MeV 
Energy=100-10000 MeV |
Comptel
|
X-ray:
X-rays show particles at very high temperatures and according to the Chandra X-ray Observatories education pages "it takes gigantic explosions, or intense magnetic or gravitational fields to energize particles to these high temperatures". They also mention that X-ray sources can be found in neutron stars and black holes or even in the space between galaxies.
The first two of the images below have the same problem as the Gamma-ray
images, the resoution isn't really fine enough to see anything much, and
what there is to see isn't much different than the surrounding area. The
Rass-Cont Broad image shows more detail but also shows there is
nothing to see in the vicinity of Arp 273. It seems there are
no x-ray sources associated with these galaxies.
HEAO 1 A-2
Frequency=2 EHz (2-20KeV) |
RASS 3/4 keV
|
Rass-Cont Broad |
HEAO 1 A-2 and RASS 3/4 keV have a field of view of 5 degrees and the Rass-Cnt Broad image has a field of view of 40.2 arcminutes.
***For information on any of the surveys from Skyview visit the Survey Information
Page***
EUV (extreme ultra-violet):
Again this image mostly serves to show that there isn't any detectable EUV radiation in the vicinity of Arp 273
EUVE 38 A
Wavelength=38 angstroms |
The field of view of this image is 40.2 arcminutes
UV:
All the images of Arp 273 and region in UV are completely solid values under 5 degrees and so that really tells us nothing about what's going on around our object of interest.
Optical:
We see here the two objects that make up Arp 273 as we expect to find them in our images. The radiation emitted in the optical part of the spectrum is visible light from stars and emission lines from gas clouds.
Digital Sky Survey
Wavelength=J or E Band |
The Field of View is 0.05 degrees
***For information on any of the surveys from Skyview visit the Survey Information
Page***
Infrared:
We can see from these images that the infrared radiation seems to correspond with the optical image, this is not surprising as the infrared radiation in these surveys is near-infrared and generally associated with Red Giants and other cooler/redder stars ( The IPAC/NASA Infrared Astronomy page - IR regions). The infrared radiation will also be contributing to the image taken at the Glenlea Astronomical Observatory as the CCD chip we are using is very sensitive in detecting both the red and infrared wavelenghts. (and if you are concerned about absorption levels of infrared light in the atmosphere due to humidity, know that a Winnipeg winter is cold and dry).
2MASS-J
Wavelength=240 THz (1.25 microns) |
2MASS-H
Wavelength=180 THz (1.65 microns) |
2MASS-K
Wavelength=138 THz (2.17 microns) |
the field of view on these images is 2.7 arcminutes
Radio:
An important emission line in the radio portion of the spectrum is the HI or 21 cm line which is given off by the neutral gas in the galaxy (which is why so many data points for this galaxy have been measured there). This is used to study the kinematics of the galaxy among other things. The emission line however is too narrow to look for in a survey. The Radio contiuum is generated by electrons spiraling in a magnetic field (cycltron radiation) (NASA's Multiwavelenth Astronomy Education page). Both galaxies have radio emmission associated with them but interestingly the smaller galaxy is brighter in radio emission. What this means is either that because it's edge on we see more cyclotron radiation or it might mean that it's simply more active over all (this wouldn't be too surprising as this is a potential result of interactions and other research on this pair seems to support this).
VLA NVSS (1.4 Ghz)
Wavelength=1.4 GHz Continuum |
WENSS
Wavelength=325 MHz Continuum |
The field of view of the VLA NVSS (1.4 Ghz) and the WENSS images are 4 arcminutes
***For information on any of the surveys from Skyview visit the Survey Information Page***
