Bursts, Pulses and Flickering: Exploring the Transient Sky So what do we expect to find? As we know, There are known knowns. There are things we know we know. We also know There are known unknowns. That is to say We know there are some things We do not know. But there are also unknown unknowns, The ones we dont know We dont know. US Sec Def. Donald Rumsfeld, DoD briefing, 12 Feb 2002 So what do we expect to find? Supernova Asteroid Transients TNO Known knowns Planet Collisions Brown Dwarf Flares Flare Stars Pulsars X-ray Binaries Supernovae Gamma Ray Bursts Variable AGN Gravitational lensing Dust echoes Known knowns Known unknowns Discovered in 2002 — Hyman et al. 2005, Nature, 234, 50 1 Jy bursts, 10 mins long, every 77 minutes Unknown unknowns Gravitational Waves Sources Neutrino Sources Cosmic Ray Sources Explosive transients Stellar Flares (impressive but not explosive) Novae Supernovae GRB Afterglows Magnetar Flares Stellar flares Explosive transients 1045 Pair Production Supernovae 1044 SNeIa 1043 1042 SNeIb/c TypeII BSG (SN1987A) Luminosity (ergs/sec) 1041 TypeII RSG (SNIIP) IMBH + WD Collision 40 10 NS + BH Collision NS + NS binaries 1039 50 100 150 200 Days Since Explosion Kasen & RR Supernovae expected rates IIP: z < 0.1; Ia: z < 0.15 1 yr, 45 epochs 1000 deg2 → 900 Ia, ~300 IIP utility relative immunity to dust → low z anchor for cosmology bolometric energy → progenitor details known unknowns in core-collapsed supernovae: peak-brightness distribution, relative fractions of the sub-types, statistical properties in general (e.g. rates as a function of galaxy SFR). K 5 much of bolometric energy in IR H at late times t J e s f f O 10 i’ + e d u r’ t i n g V a 15 M B d r U a d n a t S 20 SN 2006jc 25 0 50 100 150 Days after B max Modjaz et al. 08 Galactic Structure & Local Distance Ladder RR Lyrae & Cepheids ☞ light curves less sensitive to metallicity so (theoretically) more standard parallax with Gaia Del Principe et al. 05 SMBH: accretion flares SMBH: accretion flares SMBH: stellar ingestion X-ray binaries Neutron stars: soft x-ray transients neutron star soft X-ray transient binary system Aql X-1 since 1998. black hole candidates Long-term monitoring of the black hole candidate GX 339-4 2 Gamma-Ray PulPulsarssar Multiwavelength Light Curves The telescopes on the Compton Gamma Ray Observatory identified seven or more gamma-ray pulsars, some with very high confidence and others with less certainty. Figure 1 shows the light curves from the seven highest-confidence gamma-ray pulsars in five energy bands: radio, optical, soft X-ray (<1 keV), hard X-ray/soft gamma ray ( 10 keV - 1 MeV), and hard gamma ray (above 100 MeV). Based on th∼e detection of pulsations, all seven of these are positive detections in the gamma- ray band. The weakest (PSR B1951+32) has a statistical probability of 9 occurring by chance of 10− . Some important featu∼res of these pulsar light curves are: Crab Crab B1509-58 Vela B1706-44 B1951+32 Geminga B1055-52 r a t s n o r Radio t u ? e n e h t f o Optical n o i t a t o r e Soft n o X-Ray g n i r u d n X-ray/ o i t Gamma a i r Ray a v y t i s Hard n e Gamma t n I Ray P ~ 33 ms P ~ 150 ms P ~ 89 ms P ~ 102 ms P ~ 39 ms P ~ 237 ms P ~ 197 ms djt 7/03 Figure 1. Light curves of seven gamma-ray pulsars in five energy bands, from left to right in order of characteristic age. Each panel shows one full rotation of the neutron star. The X-ray and gamma-ray references are those from Fig. 1 of Thompson (2001), with the addition of the X-ray data for PSR B1706 44 from Gotthelf, Halpern, and − Dodson (2002). Radio references (left to right): Manchester, 1971; Ulmer et al., 1993; Kanbach et al., 1994; Johnston et al., 1992; Kulkarni et al., 1988, Kuz’min and Losovskii, 1997; Fierro et al., 1993. Optical references: Crab, Groth, 1975; Vela, Manchester et al., 1980; Geminga, Shearer et al., 1998. Panchromatic! Gravitational Wave & Neutrino Follow-up E&M connection to the next generation observatories e.g. LIGO-II to see NS-NS spiral > 100 Mpc several tens event per year but with localization accuracy ~1 deg radius SASIR: unique FOV + aperture, well-suited to rapid follow-up Advanced LIGO (2009): If we have a nearby event from a NS binary, we should hear it! Serious Design Issues & questions • construction of a 6.5m + primary (+secondary?) with fast optics (f/2.5) & wide FOV (~0.8 deg sq.) • reduced radiative heat load for IR •cadences: many surveys in one (“shallow”, “medium”, “deep”) to accommodate science •data flow, data serving Serious Design Issues & questions.