DISTRIBUTION OF HOT INTERSTELLAR MEDIUM IN EARLY-TYPE GALAXY NGC4325
Keywords:
Galaxies, Individual(NGC4325), HOT ISMAbstract
Objective: To study morphology of the hot ISM in the environment of near by early type galaxy NGC4325 at redshift z=0.025714 using 30 ks X-ray data acquired from the archive of Chandra X-ray Observatory. The hot interstellar medium (ISM) in early-type galaxies plays a crucial role in understanding their formation and evolution.
Materials and Method:NGC 4325 has been observed by the Chandra Advanced CCD Imaging Spectrometer (ACIS-S) for 30 ks on 4 February 2003 (ObsID 3232) in very faint mode. We acquired level 1 event file corresponding to this observation from the Chandra archive and reprocessed it using the calibration files provided by the Chandra X-ray Center (CALDB V 4.6.7).
Results:. Tricolor map in soft ,mid and hard band revels that the contribution of soft and mid component is more in this galaxy while hard component is very less. The best fit wabs*apec model yielded into the minimum χ2 = 0.9240 for 300 dof and the best fit temperature equal to 2.9549 keV, metallicity equal to 0.0225Z⊙, where as the 0.5-7 keV X-ray luminosity equal to 1.8068*10+42 erg/s.
Conclusion: Systematic analysis of Chandra archive data on the X-ray bright NGC4325 revels that it consist substantial amount of hot ISM
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