wednesday, november 19, 201415 years of chandra: chandra and the x-ray view of tdes, peter maksym 1...

Wednesday, November 19, 2014 15 Years of Chandra: Chandra and the X-ray View of TDEs, Peter Maksym

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Chandra and the X-ray Viewof Tidal Disruption Events

Peter Maksym Peter Maksym University of AlabamaUniversity of Alabama

[email protected]@ua.edu, @StellarBones, @StellarBonesLeft: A1795 X-ray/optical CXO/Maksym et al./Donato et al press release, 2014; Right: Maksym et al. 2013


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X-ray Selection and Follow-up


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Chandra and ROSAT flares

First TDEs seen in ROSAT NGC 5905 (Bade et al.,

1996) RX J1242-11A (Komossa

& Greiner, 1999) RX J1624+75 (Grupe et

al., 1999) RX J1420+53 (Greiner et

al, 2000)Chandra follow-up with Halpern et al. (2004, left) critical to:

Demonstrate nuclear location

Eliminate confusion Sensitivity: 10-yr extreme

(x6000) variability Spectral hardening? Still

relatively soft


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Follow-up of UV/Optical Flares

UV/X-ray – extremely important for distinguishing optical TDEs fromnuclear SNeX-ray Detections:

Gezari et al. (2006, 2008, upper-right) – Chandra D3-13

ruled out pre-existing AGN with deep AEGIS observations L

X~1043 erg/s, Γ~7, ~day-scale variability ~1 year post-disruption

D1-9 L

X~3.5 x 1041 erg/s, 2 years post-disruption

X-rays require hotter temperatures than UV blackbody trace different radii, physical regimes: inner disk, debris near R

d Arcavi et al. (2014) – Swift

PTF 09axc, ~7 x 1042 erg/s ~5 years post-disruptionNon-detections

Gezari et al. (2009) – Chandra D23H-1

LX<1041 erg/s, 3 days & 116 days post-disruption

Gezari et al. (2012 – lower right) – Chandra PS-10jh – disrupted helium core or (Guillochon 2014) ordinary?

Lx<5.8 x 1041 erg/s, >200 days post-peak

Arcavi et al. (2014) – Swift PTF 09ge (<2 x 1042 erg/s), 09djl (<2 x 1043 erg/s), ~5 years post-

disruption


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Finding (and following) TDEs with Chandra

Variability search in CDF: Luo et al. (2008) – upper limits, no detections ..but see Luo et al. (2014) Atel 6625 – possible TDE at z~1.5 ?!?

CXO J033831.8-352604 – Gradually decaying ULX in GC of NGC 1399 (Fornax) [O III] and [N II] but no Balmer... evidence for a TDE? (Irwin et al, 2010, left) Consistent with TDE of red clump HB star by 50-100 Msun BH (Clausen et al.,

2012)

See also poster by Dacheng Lin – late-term Chandra follow-up of 2XMMi J184725.1-631724 (identified in Lin et al., 2011 – right)


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Relativistic Flares!

Swift J1644+57: multiple Swift-BAT triggers, regular monitoring for 3+ years Breaks the mold: Hard Spectrum, attributed to beamed line-of-sight jet (blazar

analogue) (Levan et al., 2011; Burrows et al., 2011; Bloom et al., 2011; many subsequent papers)

Extremely bright; ~1048 erg/s inferred Fits t-5/3 decay for >1 yr, but highly variable – large epoch-to-epoch variations First ~500 days emission probably due to internal dissipation of jet (Burrows et al.,

2011; Bloom et al., 2011, Zauderer et al, 2011, Metzger et al, 2012, Liu et al, 2012, Zou et al, 2013)

Dramatic transition! Jet shuts off Chandra observation at ~610 days: Too hard disk accretion. Consistent with a

forward shock? Zauderer et al (2013, UR) Inverse compton cooling in an external shock? (Kumar et al., 2013)

Swift J2058+05: Another relativistic flare (Cenko et al., 2012; top, LR)

Both flares localized with Chandra HRC


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Tidal Disruptions in Galaxy Clusters

UL: CXO/Maksym et al./Donato et al. press releaseUR: Maksym et al. (2013) –A1795LR: Maksym et al. (2010) -A1689


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Tidal Disruptions in Galaxy Clusters

UL: Cappeluti: ROSAT & optical, w/X-ray error circlesUR: WINGS J1348 in A1795, XMM(<500 eV) blue, Gemini red, XMM (2 arcsec) and Chandra (<0.5 arcsec) error circles (See Maksym et al. 2013; 2014; Donato et al., 2014)


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What Don't We know?

How common is X-ray emission from TDEs?Is there a dichotomy between X-ray selected flares (e.g. via ROSAT, XMM-Newton [Esquej et al., 2007; 2008; Lin et al., 2011]) and optically selected flares with upper limits?How well do existing multi-band models describe X-ray evolution beyond t-5/3 (e.g. Lodato & Rossi 2009; 2011; Strubbe & Quataert 2009; 2011; Guillochon et al, 2014) Can super-Eddington accretion smother the X-ray emission (e.g. “Dougie” from ROTSE; Vinko et al., 2014)Does X-ray emission require a preferred viewing angle?Could X-ray emission occupy a preferred “phase” of TDE evolution?

Modulated accretion rate (Lodato & Rossi, 2011) Evolving debris covering fraction (Strubbe & Quataert, 2009) Changing opacity Changing temperature (Lodato & Rossi 2011)

How common are jets, and how do they form?What about X-ray emission/absorption lines/edges? (e.g. Strubbe & Quataert 2011) What can we learn from PDS analysis (e.g. Lin et al., 2011; Reis et al., 2012)


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Where Should We Go?

Solid physical basis for optical selection Important groundwork before LSST can be used for

statistical purposesMore X-ray selected events with prompt multi-wavelength follow-up

Chandra/XMM cluster monitoring? It would take an XVP

TDEs are rare, so TDE “surveys” need to be parasitic by nature

Sociological paradigm shift If you're not interested in your point sources,

share them... ...or don't share – but do check!

eROSITAAggressive X-ray follow-up of low-z optical flares

Abundance of data – easier to rule out AGN Good astrometry – easier to rule out SNe Swift can select, follow-up with Chandra/XMM

Long-term monitoring – Early & Late Easiest for bright, nearby flares Check e.g. for corona formation Cooling out-of-band (e.g. Lodato & Rossi, 2011) Frequent enough to ignore stochastic variability (see,

e.g. Liu et al., 2014)

Maksym et al., 2014, based on Lodato & Rossi 2011; See also Khabibullin & Sazonov, 2014

wednesday, november 19, 201415 years of chandra: chandra and the x-ray view of tdes, peter maksym 1...

Documents

years of chandra

chandra d23h

chandra observation

xray view of tdes

term chandra followup

chandra variability

upperright chandra d3

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