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 =c/vs:

• Optically thick wind, ~1 breakout:

• EX, T R, vs ; Consistency: t~R/c.

• Ejecta/Wind Non-T X-rays:

keV.

/2.0erg,

/102

,/

2.0/v

5.01205.0

Sun

2.0

BO7.1

124.0Sun

6.046

BO

3.0124.0

Sun

6.0

maxs,maxs,

5151

51

RMM

ETR

MM

EE

RMM

Ec

keV.1.0erg,103 4/112

3BO

212

446BO

RTRE

.s

erg,min10

3/247,3/1

42,40

synIC,

day

day1,1, t

EtLL k

SNee

XRO 080109-SN 2008D

• XRO: EX~3x1046erg, R~ct~1012cm (~1)

R*~1011cm Wind, mdot~few.

• Late non-T X (LX~1040td-0.7erg/s)+ radio

mdot~1 (@ 1015cm) wind + 1047erg, ~0.3 shell

• T=0.1keV? No! Non-thermal, dlog n/dlog E~ -2

• Jets? Or- Non-LTE X-rays in fast (v/c>0.1) breakouts:

keV.)2.0/(10

,/

2.0/v

4maxs,sBO,

3.0124.0

Sun

6.0

maxs,maxs,51

T

RMM

Ec

[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 triggerAccurate timing (hr models, , GW)EX, T R, vs

LL-SN-GRBs: E~1049erg, h<300keV, smooth L(t)–

Jets or EK~1049.5 erg, ~0.8 breakouts? Consistent with properties of 980425/SN1998b, 031203/SN2003lw, 060218/SN2006aj; 98bw late radio + X: now jet, EK~1049.5 erg, ~0.8 shell;

Challenges: EK(~0.8)/EK,tot~10-2 [Anisotropy, Failed Jet?].

X-ray: fluxes & rates

• 50SN/yr to 30Mpc• SN BO’s:

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

keV.)2.0/(10

s,30/erg/s,10erg,10

4maxs,sBO,

12230

7.0125.8

BOX,46

BOX,

T

RcRD

RfE

X-ray: Detectors

Required:• ~ 1• f < 10-9 erg/s (~10s)• ~ follow up FOV

The UFFO Pathfinder

arXiv:0912.0773

Summary- X

• Identify transients, distribute alerts Required: ~ 1, f < 10-9 erg/s (~10s), ~ 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:

• Measure R ( from T), EK (@ m/M~0.003)

• Complications: Extinction, opacity E.g. No of H recombination @ 1eV Constrain envelope composition

serg/cm10~erg/s,/

/10~

eV,/1

22

Mpc30

1211UV

1/3-day127.0

Sun

9.08.042

bol.

1/2-day

4/112

27.0eff.

51

D

RftR

MM

EmL

tRmT

pT

pT

2008D: Determine R* & Reddening

Scaling t, f:

etFtftT

T

tT

tT

r

Dttf

tTtttT

)(),()()(

)()],(,[

~

)()],([5

col.

0

4

phot.

col.

2

phot.

col.0col.

[Rabinak 10]

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))

• 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

[Rabinak 10]

[Mazzali et al. 08, Tanaka et al. 09]

[Mazzali, priv. comm.]

[Soderberg et al. 08]

[Tanaka et al. 09][Modjz et al. 09]

UV/O model[Tanaka 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 wide-field, moderately sensitive instruments

• Combination with X or optical may be powerful• Contamination by stars and AGN is a major

issue