Access to Astronomical Catalogues

← Click to display the menu
J/A+A/397/473       HST photometry of M51 cluster            (Bik+, 2003)

Clusters in the inner spiral arms of M51: The cluster IMF and the formation history. Bik A., Lamers H.J.G.L.M., Bastian N., Panagia N., Romaniello M. <Astron. Astrophys. 397, 473 (2003)> =2003A&A...397..473B
ADC_Keywords: Galaxies, photometry ; Associations, stellar Keywords: galaxies: individual: M 51 - galaxies: interactions - galaxies: spiral - galaxies: starburst - galaxies: star clusters Abstract: We present the results of an analysis of the HST-WFPC2 observations of the interacting galaxy M 51. From the observations in 5 broadband filters (UBVRI) and two narrowband filters (Hα and [OIII]) we study the cluster population in a region of 3.2x3.2kpc2 in the inner spiral arms of M 51, at a distance of about 1 to 3kpc from the nucleus. We found 877 cluster candidates and we derived their ages, initial masses and extinctions by means of a comparison between the observed spectral energy distribution and the predictions from cluster synthesis models for instantaneous star formation and solar metallicity. Description: M 51 was observed with HST-WFPC2 as part of the HST Supernova INtensive Study (SINS) program (Millard et al., 1999ApJ...527..746M). For this study we use the images taken in the broad band filters F336W (U), F439W (B), F555W (V), F675W (R) and F814W (I) from the SINS program and in the narrow band filters F502N ([OIII]) and F656N (Hα) from the GO-program of H. C. Ford. The image in U was taken on 1994 May 12, the BVRI images were taken on Jan. 15 1995 and the [OIII] and Hα images on Jan. 25 1995. The U and B images were split into three and two exposures of 400s and 700s respectively. The [OIII] and Hα images are split into two exposures of 1200s and 500s ([OIII]) and 1400s and 400s (Hα). In the remaining bands one single exposure of 600s was taken. The data was processed through the PODPS (Post Observing Data Processing System) for bias removal, flat fielding and dark frame correction. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table4.dat 99 881 *Coordinates and HST-WFPC2 broad-band photometry of 881 clusters in the inner regions of the M51 table5.dat 61 114 *Coordinates and HST-WFPC2 narrow-band Hα and [OIII] photometry of 114 sources in the inner regions of the M51.
Note on table4.dat: Photometry and coordinates by Nate Bastian, Oct 2001 Note on table5.dat: Photometry and coordinates by Nate Bastian and Henny Lamers, Oct 2001
Byte-by-byte Description of file: table4.dat
Bytes Format Units Label Explanations
1- 3 I3 --- Cl Index number of all point sources ([BLB2003] Cl NNN in Simbad) 5- 8 I4 --- Seq Old index number 10- 16 F7.3 pix Xpos X-coordinate of the HST-WF2 chip (G1) 18- 24 F7.3 pix Ypos Y-coordinate of the HST-WF2 chip (G1) 26- 29 F4.2 mag F255W [0.00] F255W filter magnitude (not observed) 31- 34 F4.2 mag e_F255W [9.99] rms uncertainty on F255W (not observed) 36- 40 F5.2 mag F336W ?=99.99 or 0.00 F336W (U) filter magnitude (2) 43- 46 F4.2 mag e_F336W ?=9.99 rms uncertainty on F336W (2) 48- 52 F5.2 mag F439W ?=99.99 or 0.00 F439W (B) filter magnitude (2) 55- 58 F4.2 mag e_F439W ?=9.99 rms uncertainty on F439W (2) 60- 64 F5.2 mag F555W ?=0.00 F555W (V) filter magnitude (2) 66- 69 F4.2 mag e_F555W ?=9.99 rms uncertainty on F555W (2) 71- 75 F5.2 mag F675W ?=0.00 F675W (R) filter magnitude (2) 77- 80 F4.2 mag e_F675W ?=9.99 rms uncertainty on F675W (2) 82- 86 F5.2 mag F814W ?=99.99 or 0.00 F814W (I) filter magnitude (2) 89- 92 F4.2 mag e_F814W ?=9.99 rms uncertainty on F814W (2) 94 A1 --- q_F255W Observation in F255W filter information (3) 95 A1 --- q_F336W Observation in F336W filter information (3) 96 A1 --- q_F439W Observation in F439W filter information (3) 97 A1 --- q_F555W Observation in F555W filter information (3) 98 A1 --- q_F675W Observation in F675W filter information (3) 99 A1 --- q_F814W Observation in F814W filter information (3)
Note (2): Magnitudes in the VEGAMAG system, Holtzman et al., 1995PASP..107..156H 0.00 means: not observed (outside the observed field) 99.99 means: source too faint, only lower magnitude limit Lower magnitude limits: F336W=20.0, F439W=22.0, F555W=22.0, F675W=21.5, F814W=21.0 (see paper) Note (3): Code that summarizes the observations 0 = not observed (outside observed HST-field), 1 = observed magnitude 9 = lower magnitude limit only
Byte-by-byte Description of file: table5.dat
Bytes Format Units Label Explanations
1- 3 I3 --- HA Sequential number of Hα sources ([BLB2003] HA NNN in Simbad) 5- 7 I3 --- Cl Corresponding number in table4 9- 15 F7.3 pix Xpos X-coordinate of Halpha source on HST-WF2-chip (G1) 17- 23 F7.3 pix Ypos Y-coordinate of Halpha source on HST-WF2-chip (G1) 25- 29 F5.2 mag F656N F656N (Hα) filter magnitude 31- 34 F4.2 mag e_F656N rms uncertainty on F656N 36- 40 F5.2 mag F502N ?=0.00 F502N ([OIII]) filter magnitude 43- 46 F4.2 mag e_F502N ?=9.99 rms uncertainty on F502N 48- 52 F5.2 mag F814W F814W (I) filter magnitude 54- 57 F4.2 mag e_F814W rms uncertainty on F814W 59 I1 --- OverHa [0/2] Position-overlap of Halpha source and F814W-source (1) 61 I1 --- OverOIII [0/2] Position-overlap of [OIII]-source and F814W-source (1)
Note (1): Position-overlap codes: 1 or 2: position overlap is okay (Δx<1.5 and Δy<1.5 pix) 0: position overlap is suspect = (1.5<Δx<2.0 or 1.5<Δy<2.0 pix)
Global notes: Note (G1): Pixels identification: (x= 1, y= 1) is RA=13h 29m 55.90s, DE=+47° 11' 27.2" (2000) (x=800, y=800) is RA=13h 29m 57.94s, DE=+47° 13' 16.6" (2000)
History: From electronic version of the journal
(End) James Marcout, Patricia Bauer [CDS] 07-Mar-2003
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

catalogue service