J/A+A/686/A241 AstroSat photometry of NGC 7469/IC 5283 SFRs (Samantaray+, 2024)
AstroSat observations of interacting galaxies NGC 7469 and IC 5283.
Samantaray A.S., Jassal H.K., Singh K.P., Dewangan G.C.
<Astron. Astrophys. 686, A241 (2024)>
=2024A&A...686A.241S 2024A&A...686A.241S (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, galaxy ; Galaxies, photometry ; Photometry, ultraviolet
Keywords: galaxies: interactions - galaxies: photometry - galaxies: Seyfert -
galaxies: star formation
Abstract:
We carry out deep near-ultraviolet (NUV) and far-ultraviolet (FUV)
imaging of an interacting galaxy system, comprised of a Seyfert type 1
galaxy NGC 7469 and its companion IC 5283. Our aim is to resolve and
map the star-forming regions in the outer arms and look for signs of
interaction between the two galaxies.
We used AstroSat Ultra Violet Imaging Telescope (UVIT) to obtain NUV
and FUV images of NGC 7469 in a range of filters. We have carried out
photometry of star-forming regions in the two galaxies and found their
spatial distributions. We also obtained the distributions of star
formation rates (SFR) in NGC 7469 and IC 5283 using the estimates
obtained from the FUV and NUV bands. We also carried out
Kolmogorov-Smirnov tests to look for differences in the SFRs in the
two galaxies. We derived the spectral energy distribution (SED),
leading to the determination of physical parameters, including the
overall SFR, stellar mass (M*), dust mass (MDust), and specific star
formation rates (sSFRs) in both the galaxies.
Our NUV and FUV images show the presence of an outer spiral arm that
is better resolved. We have identified 33 new star-forming regions out
of 51 total identified in the UVIT composite image. Enhanced star
formation activity is observed to coincide with the interaction, and
KS tests show that there are no significant differences in the SFR
distributions of NGC 7469 and IC 5283, indicating that the interaction
between the galaxies has not influenced their star formation processes
differently. The SED plots and the photometric results demonstrate
that most of the star formation activity is confined inside the
central starburst (SB) ring.
Description:
We have carried out photometry of various star-forming regions in the
two galaxies NGC 7469 and IC 5283 using Source Extractor (SExtractor)
and obtained their distribution and extracted various parameters. We
have obtained the distributions of star formation rates (SFR) in two
galaxies using the estimates obtained from the FUV and NUV bands and
carried out Kolmogorov-Smirnov tests to look for differences in the
sizes and the SFR distribution of the clumps in the two galaxies.
SExtractor measured parameters of the SF regions in various UVIT
onboard AstroSat filters for NGC 7469/IC 5283.
Objects:
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RA (2000) DE Designation(s)
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23 03 15.62 +08 52 26.0 NGC 7469 = LEDA 70348
23 03 17.98 +08 53 36.8 IC 5283 = LEDA 70350
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
uvitphot.dat 202 126 UVIT/AstroSat photometry for identified regions
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Byte-by-byte Description of file: uvitphot.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- ID ID, ANN (1)
5- 16 F12.8 deg RAdeg Right Ascension (J2000)
18- 30 F13.11 deg DEdeg Declination (J2000)
32- 49 F18.16 arcsec MajDiam Major axis length
51- 68 F18.16 arcsec MinDiam Minor axis length
70- 76 F7.2 deg PA [] Angle of the ellipse wrt x horizontal
78- 87 F10.4 ct Counts Counts
89- 97 F9.5 ct e_Counts Counts error
99-117 F19.16 kpc Dist Distance from AGN
119-138 F20.16 mJy Flux UVIT/AstroSat flux of the clump
140-158 F19.17 mJy e_Flux UVIT/AstroSat flux error of the clump
160-179 F20.18 10-2Msun/yr SFR SFR of the clump
181-202 F22.20 10-2Msun/yr e_SFR SFR error of the clump
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Note (1): SF regions in the UVIT filters for ID column is:
L = regions in N245M
R = regions in N279N
M = regions in F154W
T = regions in F172M
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Acknowledgements:
Abhinna Sundar Samantaray, abhinna.samantaray(at)uni.heidelberg.de
(End) Patricia Vannier [CDS] 29-Feb-2024