J/ApJS/269/42 9-month HST NUV survey of M87. I. LCs of 94 novae (Shara+, 2023)
A 9 month Hubble Space Telescope near-UV survey of M87.
I. Light and color curves of 94 novae, and a redetermination of the nova rate.
Shara M.M., Lessing A.M., Hounsell R., Mandel S., Zurek D., Darnley M.J.,
Graur Or, Hillman Y., Meyer E.T., Mikolajewska J., Neill J.D.,
Prialnik D., Sparks W.
<Astrophys. J. Suppl. Ser., 269, 42 (2023)>
=2023ApJS..269...42S 2023ApJS..269...42S
ADC_Keywords: Novae; Photometry, UBV; Colors; Photometry, HST
Keywords: Classical novae ; Giant elliptical galaxies
Abstract:
M87 has been monitored with a cadence of 5 days over a span of
9 months through the near-ultraviolet (NUV; F275W) and optical (F606W)
filters of the Wide Field Camera 3 (WFC3) of the Hubble Space
Telescope. This unprecedented dataset yields the NUV and optical light
and color curves of 94 M87 novae, characterizing the outburst and
decline properties of the largest extragalactic nova dataset in the
literature (after M31 and M81). We test and confirm nova modelers'
prediction that recurrent novae cannot erupt more frequently than once
every 45 days, show that there are zero rapidly recurring novae in the
central ∼1/3 of M87 with recurrence times <130d, demonstrate that
novae closely follow the K-band light of M87 to within a few arcsecs
of the galaxy nucleus, show that nova NUV light curves are as
heterogeneous as their optical counterparts, and usually peak 5-30d
after visible light maximum, determine our observations' annual
detection completeness to be 71%-77%, and measure the rate Rnova of
nova eruptions in M87 as 352-37+37yr-1. The corresponding
luminosity-specific classical nova rate for this galaxy is
7.91-1.20+1.20/yr/1010L☉,K. These rates confirm that
ground-based observations of extragalactic novae miss most faint, fast
novae and those near the centers of galaxies. An annual M87 nova rate
of 300 or more seems inescapable. A luminosity-specific nova rate of
∼7-10/yr/1010L☉,K in all types of galaxies is indicated by the
data available in 2023.
Description:
The HST observing campaign of M87 (Proposal ID: 14618; PI: Shara) was
conducted over the course of 260 days using the Wide Field Camera 3
(WFC3) F275W and F606 filters (hereafter U and V respectively). The
first observations were taken on 2016 November 13, with the last
completed on 2017 July 31. During each of the 53 epochs HST was
scheduled to observe the center of M87 for a total 720s exposure in
the F606W filter and 1500s in the F275W filter. Figure 1 shows the HST
fields of view (FOV) of those 53 epochs.
Objects:
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RA (ICRS) DE Designation(s)
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12 30 49.42 +12 23 28.0 M87 = NAME Virgo Galaxy
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 91 94 Positions, peak magnitudes, and decline times
of M87 novae
table3.dat 65 4982 M87 nova lightcurve data
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See also:
B/hst : HST Archived Exposures Catalog (STScI, 2007)
J/AJ/131/866 : Hot populations in M87 globular clusters (Sohn+, 2006)
J/ApJS/182/216 : Surface photometry of Virgo ellipticals (Kormendy+, 2009)
J/AJ/140/34 : Classification of nova light curves (Strope+, 2010)
J/ApJS/227/1 : HST survey for novae in M87. I. VI LCs (Shara+, 2016)
J/ApJ/912/19 : Follow-up phot. & sp. of 12 PGIR novae (De+, 2021)
J/ApJ/923/239 : An R-band survey of novae in M83 (Shafter+, 2021)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Seq [1/94] Nova index number from this work
4- 8 F5.2 arcsec Dist [3.9/100] Radial distance from M87 center
10- 11 I2 h RAh [12] Hour of Right Ascension (J2000)
13- 14 I2 min RAm [30] Minute of Right Ascension (J2000)
16- 20 F5.2 s RAs [43.7/53.3] Second of Right Ascension (J2000)
22 A1 --- DE- [+] Sign of the Declination (J2000)
23- 24 I2 deg DEd [12] Degree of Declination (J2000)
26- 27 I2 arcmin DEm [22/24] Arcminute of Declination (J2000)
29- 33 F5.2 arcsec DEs Arcsecond of Declination (J2000)
35 A1 --- l_Vmag Limit flag on Vmag (1)
37- 41 F5.2 mag Vmag [21.5/26] Apparent V band Vega magnitude at
peak
43 A1 --- l_Umag Limit flag on Umag (1)
45- 49 F5.2 mag Umag [20.5/25]? Apparent U band Vega magnitude at
peak
51- 55 F5.2 mag (U-V)Vp [-2.5/2.3]? The (U-V) color at peak V band
magnitude
57- 61 F5.2 mag (U-V)Up [-3/0.9]? The (U-V) color at peak U band
magnitude
63- 67 F5.2 mag (Up-Vp) [-2.5/1.1]? The U band peak minus V band peak
color
69- 73 F5.2 d Vt1 [2/24]? Time to decline one magnitude from
peak V band
75- 79 F5.2 d Ut1 [1.4/57.2]? Time to decline one magnitude
from peak U band
81- 85 F5.2 d Vt2 [4/73.2]? Time to decline two magnitude from
peak V band
87- 91 F5.2 d Ut2 [2.9/69]? Time to decline two magnitude from
peak U band
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Note (1): The inclusion of a "<" indicates that we do not think the true peak
was observed (because it was likely before or after our survey
window, or likely occurred in an epoch when it was not on the chip).
Therefore, all we can say is that the peak was something brighter
than the brightest we observed.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Seq [1/94] Nova index number from this work
4- 5 I2 --- Epoch [1/53] Epoch number
7- 12 F6.2 d D1 [0/260.3] Days since 1st Epoch (precise time of
the 1st Epoch=MJD57705.0605)
14- 20 F7.2 d DF606W [-256/261]? Days since F606W Peak
22- 28 F7.2 d DF275W [-261/261]? Days since F275W Peak
30- 30 A1 --- l_Vmag Limit flag on Vmag
32- 36 F5.2 mag Vmag [21.5/28.4]? Apparent V band HST STMAG magnitude
38- 41 F4.2 mag e_Vmag [0.01/2.1]? Uncertainty in Vmag
43- 43 A1 --- l_Umag Limit flag on Umag
45- 49 F5.2 mag Umag [20.5/25.8]? Apparent U band HST STMAG magnitude
51- 54 F4.2 mag e_Umag [0.02/1.3]? Uncertainty in Umag
56- 60 F5.2 mag (U-V) [-3.4/2.2]? The (U-V) color index
62- 65 F4.2 mag e_(U-V) [0.03/0.9]? Uncertainty in (U-V)
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 02-Feb-2024