Comet ISON February 2013 HFOSC and FOSC Observations Data Abstract ============= In February 2013, we have observed the comet ISON on three dates in R and I Bessel bands using the 2-m HCT telescope of the IIA, Hanle, India. On these dates, the weather was very bad with heavy clouds and the Moon, and though we took many exposures, on most of the frames the comet is not seen. For example, on February 19, the background was ~11,000 counts, while the comet was only ~200 counts above the background with seeing >7". On February 21, the background was ~2,800 counts and the comet of ~400 counts above the background, with seeing ~7". Though we have taken 14 exposures, only on one frame (wb210021.fits) the comet is clearly seen. On February 22, out of total 31 exposures in R, only 6 are good. Therefore, we have reduced (and aligned) only those images where the comet can be seen. The manual of the HFOSC instrument is included. Spectroscopic data was taken on February 09 using the Faint Object Spectrograph and Camera (FOSC) mounted on the 1.0-m (40") telescope T40 of the Wise Observatory of Tel-Aviv University, Israel, located in the Negev desert, near the town of Mitzpe Ramon, about 200 km south of Tel-Aviv at an altitude of 875 m above sea level. Wise Observatory FOSC instrument was used with a 15'-long 2"-wide slit aligned East-West, approximately in the direction of the apparent motion of the comet. The telescope was guided at the sidereal rate. The grism used for this observation, with 600 gr/mm, provides a dispersion of 3.1 angstrom/pixel. Along with the comet, a spectrum of approximately solar-type G8V star 55 Cnc was obtained, as well as calibration spectra of flat-field halogen lamps, bias and He-Ar lamps for wavelength calibration. The manual of the FOSC instrument is included. ---------------------------------------------- DATE-OBS Telescope Mode 2013-02-09 40" T40 Spectroscopy 2013-02-19 2-m HCT Photometry 2013-02-21 2-m HCT Photometry 2013-02-22 2-m HCT Photometry ---------------------------------------------- Data Set Overview ================= Observational Campaign Overview ================================== We have been observing the comet C/2012 S1 (ISON), obtaining spectroscopic and imaging data from three different telescopes: 2.0-m Himalayan Chandra Telescope (HCT) of the Indian Astrophysical Observatory (IAO) of the Indian Institute of Astrophysics (IIA), located at 4500 m above sea level, Hanle, Leh, Ladakh; 2.34-m Vainu Bappu Telescope (VBT) of Vainu Bappu Observatory (VBO) of the IIA, located at Kavalur, Tamil Nadu, India; and 40-inch T40 telescope of the Wise Observatory, Tel Aviv, Israel. Our observations cover nearly the whole year, from January till November 2013. In this time, the comet spanned a heliocentric distance of 5.03 - 0.68 au and geocentric distance of 4.08 - 0.94 au. These observations were planned as supplementary to our plans to observe the comet from a UV spectrograph onboard the high-altitude balloon. However, our launch has failed to obtain the spectra. Photometric data were obtained using the Himalayan Faint Object Spectrograph and Camera (HFOSC) mounted on the 2.0-m HCT of the IAO. HFOSC is equipped with a Thompson CCD of 2048 x 2048 pixels with a pixel scale of 0.296"/pix and a field of view of ~10 x 10 arcmin (Anupama, 2000). The readout noise, gain and readout time of the CCD are 4.87 e, 1.22 e/ADU, and 90 sec, respectively. Images were taken in B, V, R and I filters, depending on the month. In January, February and May observations, the telescope was moved at a sidereal rate which means that at the duration of the exposure, the comet would move slightly across the field. Observations in September and October were performed in the Keystone mode of the HCT -- the non-sidereal tracking/guiding at the rate of the proper motion of the comet. In this mode the telescope is moved at the proper motion of the comet -- which means that the comet stays in the centre of the field. The Keystone mode compatible files have been generated from the JPL/Horizons ephemeris data for the comet. In addition to photometry, we observed the comet spectroscopically with 2-m HCT, 2.34-m VBT of the VBO, India; and the 40-inch T40, Israel. Spectroscopic observations on the HCT were performed in January, May, September and October using HFOSC instrument with Grism 7 (380-684 nm) and Grism 8 (580-835 nm). The solar analog G5 HD195034 (Takeda & Tajitsu 2009) was observed in May 2014 at the same airmass as the comet to obtain the solar continuum, which was used in all spectroscopic datasets. Fe-Ar, Fe-Ne and halogen lamps were used for the wavelength calibration, and flat-fielding, respectively. In January and May observations, the telescope was moved at a sidereal rate which means that for the duration of the exposure, the comet would move slightly across the slit. Observations in September and October were performed in the Keystone mode of the HCT. The Keystone mode compatible files have been generated from the JPL/Horizons ephemeris data for the comet. Spectroscopic observations on the VBT were performed in May, October and November using a medium-resolution spectrograph from Optomechanics Research (OMR) of the VBT (Prabhu et al. 1998). Spectrophotometric standards and solar type stars were observed along with Fe-Ar, Fe-Ne and halogen lamps for flux and wavelength calibration. In all observations the slit was placed cross the nucleus for the entire duration of the observation. In May the telescope was moved at a sidereal rate. In October and November, after putting the comet on the slit at the sidereal rate, we manually guided the comet with telescope handset whenever we noticed the drift (moving away from the slit) of the comet. The observations in May were performed using a 600 lines/mm grating, whereas the October and November observations were performed using 300 lines/mm grating. Wise Observatory Faint Object Spectrograph and Camera (FOSC) instrument was used on February 9th with a 15'-long 2"-wide slit aligned East-West, approximately in the direction of the apparent motion of the comet. The telescope was moved at a sidereal rate which means that for the duration of the exposure, the comet would move slightly across the slit. The grism used for this observation, with 600 gr/mm, provides a mean dispersion of 3.1 angstr/pixel. Along with the comet, a spectrum of approximately solar-type G8V star 55 Cnc was obtained. References Anupama, G. C., 2000, Bull. Astr. Soc. India, 28, 647 (ASTRONEWS). Prabhu, T. P., Anupama, G. C., & Surendiranath, R. 1998, Bull. Astr. Soc. India, 26, 383. Takeda, Y. & Tajitsu, A. (2009). Publications of the Astronomical Society of Japan. 61, 471. Data ================= Raw and processed images and spectra are in the FITS format. Each data set has a document describing the files, directory structure, reduction procedure and description of derived products. Derived spectra are in table ascii format. Software ======== Whenever special codes were used in the data reduction, they are added to that specific dataset. Confidence Level Overview ========================= The data files in this dataset were reviewed internally by the authors.