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The association of IRAS sources and 12CO emission in the outer Galaxy
We have revisited the question of the association of CO emission withIRAS sources in the outer Galaxy using data from the FCRAO Outer GalaxySurvey (OGS). The availability of a large-scale high-resolution COsurvey allows us to approach the question of IRAS-CO associations from anew direction - namely we examined all of the IRAS sources within theOGS region for associated molecular material. By investigating theassociation of molecular material with random lines of sight in the OGSregion we were able to construct a quantitative means to judge thelikelihood that any given IRAS-CO association is valid and todisentangle multiple emission components along the line of sight. Thepaper presents a list of all of the IRAS-CO associations in the OGSregion. We show that, within the OGS region, there is a significantincrease ( ~ 22%) in the number of probable star forming regions overprevious targeted CO surveys towards IRAS sources. As a demonstration ofthe utility of the IRAS-CO association table we present the results ofthree brief studies on candidate zone-of-avoidance galaxies with IRAScounterparts, far outer Galaxy CO clouds, and very bright CO clouds withno associated IRAS sources. We find that ~ 25% of such candidate ZOAGsare Galactic objects. We have discovered two new far outer Galaxystar-forming regions, and have discovered six bright molecular cloudsthat we believe are ideal targets for the investigation of the earlieststages of sequential star formation around HII regions. Finally, thispaper provides readers with the necessary data to compare othercatalogued data sets with the OGS data.Tables 1, 2 and A1 are only available in electronic form at the CDS viaanonymous ftp to\ cdsarc.u-strasbg.fr (130.79.128.5) or via\http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/399/1083
| Multi-colour light variation of AGB stars observed with ISO
New visual light curves and infrared multi-epoch photometry arepresented for a sample of AGB-stars spectroscopically observed with ISO.While the ISO work is or will be presented elsewhere, the aim of thispaper is to give an overview of the properties of the light change ofthe objects. This information is crucial for the interpretation of thevaluable ISO material. Using the University of Vienna Twin AutomaticPhotoelectric Telescope (APT) we monitored the stars of our sample inthe photometric bands V and I_C. We present the light curve of eachobject and derive the parameters of the current light change, such asperiod(s) and amplitude. Furthermore we give V-I_C colours and colourvariations for these objects. Our results allow us to derive somegeneral results on semiregular and irregular variables. Only in lessthan 50% of the cases could we confirm the GCVS period. Moreover, we didnot find any pronounced difference between SRb and Lb variables in theregularity of the light curve. The existence of rapid oscillationsindicated by Hipparcos data could not be confirmed. In addition to thevisual light changes we present new near infrared photometry data.Although typically only few data points are available, they can beviewed relative to the better-monitored visual light curves providinginformation on possible phase shifts and differences in amplitude indifferent parts of the spectrum. Furthermore, multi-epoch photometryallows us to derive mean colours for these objects. Based onobservations made with the Carlos Sánchez Telescope operated onthe island of Tenerife by the Instituto de Astrofísica deCanarias (IAC) in the Observatorio del Teide, Izaña. Tables B2 toB5 are only available in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/375/527
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Osservazione e dati astrometrici
| Costellazione: | Cassiopea |
| Ascensione retta: | 00h51m08.08s |
| Declinazione: | +63°06'06.1" |
| Magnitudine apparente: | 8.005 |
| Distanza: | 1960.784 parsec |
| Moto proprio RA: | 1 |
| Moto proprio Dec: | -3.2 |
| B-T magnitude: | 10.084 |
| V-T magnitude: | 8.177 |
Cataloghi e designazioni:
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