J/ApJ/948/33 HST proper motion measurements of SNR N132D (Banovetz+, 2023)
Hubble Space Telescope proper motion measurements of supernova remnant N132D:
center of expansion and age.
Banovetz J., Milisavljevic D., Sravan N., Weil K.E., Subrayan B.,
Fesen R.A., Patnaude D.J., Plucinsky P.P., Law C.J., Blair W.P.,
Morse J.A.
<Astrophys. J., 948, 33 (2023)>
=2023ApJ...948...33B 2023ApJ...948...33B
ADC_Keywords: Supernova remnants; Interstellar medium; Proper motions; Optical
Keywords: Supernova remnants ; Interstellar medium
Abstract:
We present proper motion measurements of the oxygen-rich ejecta of the
LMC supernova remnant N132D using two epochs of Hubble Space Telescope
Advanced Camera for Surveys data spanning 16 years. The proper motions
of 120 individual knots of oxygen-rich gas were measured and used to
calculate a center of expansion (CoE) of α=5h25m01.71s and
δ=-69°38'41.64" (J2000) with a 1σ uncertainty of
2.90". This new CoE measurement is 9.2" and 10.8" from two previous
CoE estimates based on the geometry of the optically emitting ejecta.
We also derive an explosion age of 2770±500yr, which is consistent
with recent age estimates of ∼2500yr made from 3D ejecta
reconstructions. We verified our estimates of the CoE and age using a
new automated procedure that detected and tracked the proper motions
of 137 knots, with 73 knots that overlap with the visually identified
knots. We find that the proper motions of the ejecta are still
ballistic, despite the remnant's age, and are consistent with the
notion that the ejecta are expanding into an interstellar medium
cavity. Evidence for explosion asymmetry from the parent supernova is
also observed. Using the visually measured proper motion measurements
and corresponding CoE and age, we compare N132D to other supernova
remnants with proper motion ejecta studies.
Description:
Using the Mikulski Archive for Space Telescopes (MAST) at the Space
Telescope Science Institute, we examined three epochs of HST images
that are sensitive to [OIII]λλ4959,5007 emission tracing
the O-rich ejecta of N132D. These consist of an image taken in
1994 using the Wide Field Planetary Camera 2 (WFPC2) with the F502N
filter (PI: Blair GO-5365), a 2004 image using the the Advanced Camera
for Surveys (ACS) and the F475W filter (PI: Green GO-12001), and a
2020 image using the ACS/F475W setup (PI: Milisavljevic GO-15818). The
1994 and 2020 F502N images use different instrument and filter
configurations, whereas the 2004 and 2020 F475W images were both
obtained with ACS. The specific observations analyzed can be accessed
via DOI:10.17909/4ppy-4e90. See Section 2.
Objects:
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RA (ICRS) DE Designation(s)
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05 25 02.30 -69 38 39.0 N132D = LHA 120-N 132D
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea2.dat 84 167 *Manually inspected knot measurements and
corresponding automated measurements
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Note on tablea2.dat: Positive values indicate direction to the north and
east for RA and DE, respectively. Results of the automated procedure
are matched when applicable.
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See also:
J/ApJS/179/195 : A catalog of outer ejecta knots in Cas A (Hammell+, 2008)
J/ApJ/780/59 : The Araucaria project: EBs in SMC (Graczyk+, 2014)
J/A+A/586/A71 : LMC 0.2-100GeV images (Ackermann+, 2016)
J/ApJ/816/49 : Spitzer/IRAC observations of SMC Cepheids (Scowcroft+, 2016)
J/ApJ/915/20 : Photometry of stars in & near 1E 0102.2-7219 (Li+, 2021)
Byte-by-byte Description of file: tablea2.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Knot [1/167] Internal Knot index number
5 I1 h RAh [5] Hour of Right Ascension (J2000)
7- 8 I2 min RAm [24/25] Minute of Right Ascension (J2000)
10- 15 F6.3 s RAs Second of Right Ascension (J2000)
17 A1 --- DE- [+] Declination sign (J2000)
18- 19 I2 deg DEd [69] Degree of Declination (J2000)
21- 22 I2 arcmin DEm [38/39] Arcsecond of Declination (J2000)
24- 29 F6.3 arcsec DEs Arcsecond of Declination (J2000)
31- 37 F7.3 mas/yr pmRA-Vis [-11.2/7.1]? Visual procedure proper motion
along RA
39- 43 F5.3 mas/yr e_pmRA-Vis [0.005/0.7]? Uncertainty in pmRA-Vis
45- 50 F6.3 mas/yr pmDE-Vis [-7.8/11]? Visual procedure proper motion
along DE
52- 56 F5.3 mas/yr e_pmDE-Vis [0.06/0.7]? Uncertainty in pmDE-Vis
58- 64 F7.3 mas/yr pmRA-Auto [-12.4/10]? Automated procedure proper
motion along RA
66- 70 F5.3 mas/yr e_pmRA-Auto [0/0.7]? Uncertainty in pmRA-Auto
72- 78 F7.3 mas/yr pmDE-Auto [-13.6/13.6]? Automated procedure proper
motion along DE
80- 84 F5.3 mas/yr e_pmDE-Auto [0/0.7]? Uncertainty in pmDE-Auto
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 25-Apr-2025