HD101105 Near UV Spectra
Posted: Mon Apr 03, 2017 12:08 pm
Bonjour!
Enclosed is a spectrum of Solar Analog star HD101501 (G8V type, approximately 1.5 Gys old) processed in Isis:
A CDK17 telescope (0.43 meter) working at F/6.8 with a JTW L-200 spcroscope with a 1800 l/mm grating with a 43micron slit used with a Atik 460ex CCD,
guided with a Atik Titan was used. Seven (7)X 600 second exposures, binned 2x2 of HD101501 were used as well as a 60 second Ne-Ar calibration exposure
before and after image acquisition. A 40 minute flat (4x600 sec.) was made to get to an average ADU value of 54K.
I used spectrum of Procyon (taken at an earlier date...it clouded out before I was able to acquire a nearby A-star) as an instrument Response source for Isis.
Per previous advice, I used a the MILES source in the Isis database for a F5V to process a instrument response, via the Response button under profile, once the initial processing on Procyon was done. This required a shift of approximately -1.36A to make the Red & blue curve match as closely as possible before hitting the "Ok" button to produce Instrument response. This was saved as a .fits file and was used in the Instr. responsivity box under the Genral tab in Isis, when processing HD101501's spectra.
Since this is far off the H-Alpha region, I had to make a custom "File mode" list (under the General tab) of the He/Ar calibration lines that were in this region.
Here they are out of curiosity:
4 (# of lines-1)
0.2370 (Dispersion in A/px)
3888.65
3925.72
3948.98
4044.42
4072.01
Now I need to make another for the Hy region. Isis seems to be "ok" with these spectra, but I'll need more practice and study to make sure I'm not missing anything subtle affecting the results. Comments welcomed
James
Enclosed is a spectrum of Solar Analog star HD101501 (G8V type, approximately 1.5 Gys old) processed in Isis:
A CDK17 telescope (0.43 meter) working at F/6.8 with a JTW L-200 spcroscope with a 1800 l/mm grating with a 43micron slit used with a Atik 460ex CCD,
guided with a Atik Titan was used. Seven (7)X 600 second exposures, binned 2x2 of HD101501 were used as well as a 60 second Ne-Ar calibration exposure
before and after image acquisition. A 40 minute flat (4x600 sec.) was made to get to an average ADU value of 54K.
I used spectrum of Procyon (taken at an earlier date...it clouded out before I was able to acquire a nearby A-star) as an instrument Response source for Isis.
Per previous advice, I used a the MILES source in the Isis database for a F5V to process a instrument response, via the Response button under profile, once the initial processing on Procyon was done. This required a shift of approximately -1.36A to make the Red & blue curve match as closely as possible before hitting the "Ok" button to produce Instrument response. This was saved as a .fits file and was used in the Instr. responsivity box under the Genral tab in Isis, when processing HD101501's spectra.
Since this is far off the H-Alpha region, I had to make a custom "File mode" list (under the General tab) of the He/Ar calibration lines that were in this region.
Here they are out of curiosity:
4 (# of lines-1)
0.2370 (Dispersion in A/px)
3888.65
3925.72
3948.98
4044.42
4072.01
Now I need to make another for the Hy region. Isis seems to be "ok" with these spectra, but I'll need more practice and study to make sure I'm not missing anything subtle affecting the results. Comments welcomed
James