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J/AJ/117/1708       NGC 1741 HST photometry                  (Johnson+, 1999)

The very young starburst merger system NGC 1741. Johnson K.E., Vacca W.D., Leitherer C., Conti P.S., Lipscy S.J. <Astron. J. 117, 1708 (1999)> =1999AJ....117.1708J
ADC_Keywords: Associations, stellar ; Photometry, photographic ; Photometry, ultraviolet Mission_Name: HST Keywords: galaxies: individual (NGC 1741) - galaxies: interactions - galaxies: irregular - galaxies: photometry - galaxies: starburst - galaxies: star clusters Abstract: We use Hubble Space Telescope (HST) Faint Object Camera (FOC) ultraviolet (UV) and WFPC2 optical images in conjunction with UV spectroscopic observations taken with the Goddard High Resolution Spectrograph to examine the star formation history and properties of the interacting galaxy system NGC 1741 in the Hickson Compact Group 31. The high spatial resolution afforded by HST has allowed us to identify a large number of starburst knots, or "superstar clusters" (SSCs), in the starburst regions of this system. Photometry of these SSCs in the UV and optical bands indicates that most of these objects have ages of a few Myr, with a few up to ∼100Myr, and masses between 104 and 106M. The estimated age is confirmed by a spectral synthesis analysis of one knot for which we have obtained a UV spectrum. The V-band luminosity function of the SSCs is well represented by a power law Φ(L)∼L with an index of -1.85, with no evidence of a turnover brighter than the completeness limit. These properties are in good agreement with those found for SSCs in other starburst galaxies. Our results support the suggestion that some of these SSCs may be extremely young globular clusters formed in a relatively recent starburst episode that has been triggered by a merger event. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table2.dat 96 434 Magnitudes measured for the SSCs in NGC 1741
Byte-by-byte Description of file: table2.dat
Bytes Format Units Label Explanations
1- 3 I3 --- [JVL99] Sequential number 4 A1 --- f_[JVL99] [*] Note on [JVL99] (1) 6 I1 h RAh Right ascension (J2000) 8- 9 I2 min RAm Right ascension (J2000) 11- 15 F5.2 s RAs Right ascension (J2000) 17 A1 --- DE- Declination sign (J2000) 18 I1 deg DEd Declination (J2000) 20- 21 I2 arcmin DEm Declination (J2000) 23- 27 F5.2 arcsec DEs Declination (J2000) 29- 33 F5.2 mag F220W ? F220W magnitude 35- 38 F4.2 mag e_F220W ? rms uncertainty on F220W 40- 45 F6.3 mag F439W ? F439W magnitude 47- 51 F5.3 mag e_F439W ? rms uncertainty on F439W 53- 58 F6.3 mag F555W ? F555W magnitude 60- 64 F5.3 mag e_F555W ? rms uncertainty on F555W 66- 71 F6.3 mag F675W ? ? F675W magnitude 73- 77 F5.3 mag e_F675W ? rms uncertainty on F675W 79- 84 F6.3 mag F814W ? F814W magnitude 86- 90 F5.3 mag e_F814W ? rms uncertainty on F814W
Note (1): *: The superstar clusters (SSCs) may be marginally resolved as discussed in Sect. 3.3.
History: From electronic AJ version
(End) James Marcout, Patricia Bauer [CDS] 04-Oct-1999
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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