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Wide field X (& UV ?) Identify transients, distribute alerts Candidate X (&UV)-transients • SN breakouts • XRF’s • LL GRBs • Unknown (eg BH-Stellar disruptions)? Early SN emission • SN shock is radiation mediated at the envelope • Outer (10-3Msun) heated to ~keV • Shock emergence accompanied by thermal X-rays • Post breakout expansion early UV emission • Wind - Breakout may take place within the wind - Ejecta/wind interaction non-thermal X, radio Breakout X-rays: a simple model • At t=c/vs: b s,max v s,max / c 0.2 EBO 2 10 46 E 510.6 M / M Sun 0.4 E 510.6 M / M Sun 0.4 R120.3 , 1.7 R12 erg, TBO 0.2 E 510.2 M / M Sun 0.05 R120.5 keV. • Optically thick wind, Gb~1 breakout: EBO 3 1046 Gb R122 erg, TBO 0.1Gb R121/ 4 keV. 4 3 • EX, T R, vs ; Consistency: Dt~R/c. • Ejecta/Wind Non-T X-rays: L IC,syn 10 40 min e , 1 1/ 3 e , 1 LSN , 42 , t day Ek , 47 erg . 2/3 t day s XRO 080109-SN 2008D • XRO: EX~3x1046erg, R~cDt~1012cm (Gb~1) R*~1011cm Wind, mdot~few. • Late non-T X (LX~1040td-0.7erg/s)+ radio mdot~1 (@ 1015cm) wind + 1047erg, b~0.3 shell • T=0.1keV? No! Non-thermal, dlog ng/dlog Eg~ -2 • Jets? Or- Non-LTE X-rays in fast (v/c>0.1) breakouts: b s,max vs,max / c 0.2 E 510.6 M / M Sun 0.4 R120.3 , TBO,s 10( b s,max / 0.2) 4 keV. [Kat & Budnik 10] Some implications • XRO 080109 may be SN 2008D breakout • For reasonable explosion parameters, WR & BSG progenitors produce fast breakouts non-thermal XRO’s up to 10’s to 100’s keV • New type of SN trigger Accurate timing (hr models, , GW) EX, T R, vs LL-SN-GRBs: Eg~1049erg, h<300keV, smooth L(t)– Jets or EK~1049.5 erg, b~0.8 breakouts? Consistent with properties of 980425/SN1998b, 031203/SN2003lw, 060218/SN2006aj; 98bw late radio + X: now jet, EK~1049.5 erg, b~0.8 shell; Challenges: EK(b~0.8)/EK,tot~10-2 [Anisotropy, Failed Jet?]. X-ray: fluxes & rates • 50SN/yr to 30Mpc • SN BO’s: EX, BO 1046 erg, f X, BO 10 8.5 R120.7 erg/s, 2 D30 TBO,s 10( b s,max / 0.2) 4 keV. b dist. not known Lower threshold E? 08D based rate (95%) > 10-3/L*yr~0.1 CC SN rate • LL GRBs: EX~1048.5erg (??) ~10-5/L*yr~1/yr out to 100Mpc • ~10keV XRF’s: EX>~1048erg (??) ~10-6/L*yr~ 0.1/yr out to 100Mpc • ?? MBH Stellar disr.: 0.01Msunc2, 105(M/108Msun)s 1047erg/s R / c 30 R12 s, X-ray: Detectors Required: • DW ~ 1 • f < 10-9 erg/s (~10s) • Dq ~ follow up FOV The UFFO Pathfinder arXiv:0912.0773 Summary- X • Identify transients, distribute alerts Required: DW ~ 1, f < 10-9 erg/s (~10s), Dq ~ follow up FOV • Candidate X (&UV)-transients * SN breakouts: New SN trigger, Accurate timing (hr models, , GW); EX, T R, vs * XRF’s, LL GRBs: Sources, SN-connection, physics * Unknown (eg BH-Stellar disruptions) UV transients • Best resource is GALEX, not systematically surveyed so far • Two classes of events receive attention: UV shock breakouts and tidal disruption flares • Contamination by stars and AGN is a major issue Early UV/Optical emission • Rapid post-breakout expansion Adiabatic cooling, photosphere penetration • t>R*/vBO Predictions: Teff. 1 T / m p 0.27 1/ 4 -1/2 R12 tday eV, Lbol. ~ 1042 T / m p 0.8 E 510.9 M / M Sun 0.7 -1/3 R12tday erg/s, f UV ~ 1011 • Measure R ( from T), EK (@ dm/M~0.003) • Complications: Extinction, opacity E.g. No of H recombination @ 1eV Constrain envelope composition R12 erg/cm 2s 2 D30Mpc 2008D: Determine R* & Reddening Scaling t, fl : [Rabinak 10] lTcol.[t tl (t , l )] l0Tcol. (t ) D ~ f l [l , tl (t , l )] rphot. 2 Tcol. (tl ) Tphot.(tl ) 4 5 T0 t l f ( l , t ) F ( t ) e l l T ( t ) col. l 2008D- UV summary • Early UV/O: R*=1011cm, He with C/O Relative extinction curve, EB-V=0.6 E51/(M/Msun)~0.8 (assuming AV (EB-V)) [Rabinak 10] • Later light curve: 0.8<E/M<1.3 ~30% C at 20,000km/s 0.4<EB-V<0.8 Progenitor models: 0.9<R*/1011cm <1.5 [Mazzali et al. 08, Tanaka et al. 09] [Mazzali, priv. comm.] UV/O model [Tanaka et al. 09] [Soderberg et al. 08] [Tanaka et al. 09] [Modjz et al. 09] UV breakout rates (based on Gezari 2008, GALEX) • GALEX expected rate (optimistic?) is 2 deg-1 y-1 • If we scale the GALEX area by ~103, we can expect >10 events y-1 even if the sensitivity is 102 less. • The observed signals have UV flux~host, so confusion with (even mildly) variable sources is an issue unless additional information is available • A combined UV survey+optical SN survey like PTF will be powerful to get retrospective measurements Tidal disruption flares • A star disrupted and accreted by a dormant supermassive black hole is expected to result in a UV/X flare, several months long. • Several events claimed based on wide-field X (ROSAT) and UV (GALEX) • Major issue is confusion with AGN. UVFs • Speculative: the end of the GRB-XRF sequence would be very soft flares (UVFs). • Here, and in all other “unknowns” confusion with stars and AGN is a formidable obstacle. UV - summary • Best resource is GALEX, not systematically surveyed so far, most parameters unknown • UV shock breakouts should be accessible to widefield, moderately sensitive instruments • Combination with X or optical may be powerful • Contamination by stars and AGN is a major issue