Double-peaked Balmer Emission Indicating Prompt Accretion Disk Formation in an X-Ray Faint Tidal Disruption Event
Research output: Contribution to journal › Journal article › Research › peer-review
Standard
Double-peaked Balmer Emission Indicating Prompt Accretion Disk Formation in an X-Ray Faint Tidal Disruption Event. / Hung, Tiara; Foley, Ryan J.; Ramirez-Ruiz, Enrico; Dai, Jane L.; Auchettl, Katie; Kilpatrick, Charles D.; Mockler, Brenna; Brown, Jonathan S.; Coulter, David A.; Dimitriadis, Georgios; Holoien, Thomas W-S; Law-Smith, Jamie A. P.; Piro, Anthony L.; Rest, Armin; Rojas-Bravo, Cesar; Siebert, Matthew R.
In: Astrophysical Journal, Vol. 903, No. 1, 31, 01.11.2020.Research output: Contribution to journal › Journal article › Research › peer-review
Harvard
APA
Vancouver
Author
Bibtex
}
RIS
TY - JOUR
T1 - Double-peaked Balmer Emission Indicating Prompt Accretion Disk Formation in an X-Ray Faint Tidal Disruption Event
AU - Hung, Tiara
AU - Foley, Ryan J.
AU - Ramirez-Ruiz, Enrico
AU - Dai, Jane L.
AU - Auchettl, Katie
AU - Kilpatrick, Charles D.
AU - Mockler, Brenna
AU - Brown, Jonathan S.
AU - Coulter, David A.
AU - Dimitriadis, Georgios
AU - Holoien, Thomas W-S
AU - Law-Smith, Jamie A. P.
AU - Piro, Anthony L.
AU - Rest, Armin
AU - Rojas-Bravo, Cesar
AU - Siebert, Matthew R.
PY - 2020/11/1
Y1 - 2020/11/1
N2 - We present the multiwavelength analysis of the tidal disruption event (TDE) AT 2018hyz (ASASSN-18zj). From follow-up optical spectroscopy, we detect the first unambiguous case of resolved double-peaked Balmer emission in a TDE. The distinct line profile can be well-modeled by a low eccentricity (e 0.1) accretion disk extending out to similar to 100 R-p and a Gaussian component originating from non-disk clouds, though a bipolar outflow origin cannot be completely ruled out. Our analysis indicates that in AT 2018hyz, disk formation took place promptly after the most-bound debris returned to pericenter, which we estimate to be roughly tens of days before the first detection. Redistribution of angular momentum and mass transport, possibly through shocks, must occur on the observed timescale of about a month to create the large H alpha-emitting disk that comprises less than or similar to 5% of the initial stellar mass. With these new insights from AT 2018hyz, we infer that circularization is efficient in at least some, if not all optically bright, X-ray faint TDEs. In these efficiently circularized TDEs, the detection of double-peaked emission depends on the disk inclination angle and the relative strength of the disk contribution to the non-disk component, possibly explaining the diversity seen in the current sample.
AB - We present the multiwavelength analysis of the tidal disruption event (TDE) AT 2018hyz (ASASSN-18zj). From follow-up optical spectroscopy, we detect the first unambiguous case of resolved double-peaked Balmer emission in a TDE. The distinct line profile can be well-modeled by a low eccentricity (e 0.1) accretion disk extending out to similar to 100 R-p and a Gaussian component originating from non-disk clouds, though a bipolar outflow origin cannot be completely ruled out. Our analysis indicates that in AT 2018hyz, disk formation took place promptly after the most-bound debris returned to pericenter, which we estimate to be roughly tens of days before the first detection. Redistribution of angular momentum and mass transport, possibly through shocks, must occur on the observed timescale of about a month to create the large H alpha-emitting disk that comprises less than or similar to 5% of the initial stellar mass. With these new insights from AT 2018hyz, we infer that circularization is efficient in at least some, if not all optically bright, X-ray faint TDEs. In these efficiently circularized TDEs, the detection of double-peaked emission depends on the disk inclination angle and the relative strength of the disk contribution to the non-disk component, possibly explaining the diversity seen in the current sample.
KW - Galaxy accretion disks
KW - Black hole physics
KW - High energy astrophysics
KW - BLACK-HOLES
KW - STARS
KW - LINES
KW - PHOTOMETRY
KW - EVOLUTION
KW - PROGRAM
KW - STREAM
KW - MASSES
KW - FLOWS
KW - POWER
U2 - 10.3847/1538-4357/abb606
DO - 10.3847/1538-4357/abb606
M3 - Journal article
VL - 903
JO - Astrophysical Journal
JF - Astrophysical Journal
SN - 0004-637X
IS - 1
M1 - 31
ER -
ID: 251690924