1. Prompt GRB Follow-up Experiments with LOTIS and Super-LOTIS Collaborators: E. Ables, M. McKernan, R. Wurtz, J. Wickersham – LLNL G. Williams, P. Milne, M. Bradshaw – Steward Observatory S. Barthelmy - NASA/GSFC D. Hartmann, K. Lindsay – Clemson University K. C. Hurley – University of California, Berkeley In Collaboration with the Cal Tech GRB Group Zwicky SN Workshop Jan. 17, 2004 Hye-Sook Park Lawrence Livermore National Laboratory Livermore, CA USA

2. Gamma Ray Bursts are flashes of  -ray radiation above 0.1 MeV emanating from point sources, isotropically but inhomogenously distributed in the universe and lasting 1~1000 seconds The BATSE detectors on the CGRO satellite detect ~1 GRB everyday Most Powerful Explosion Since the Big Bang !! —NASA press release May 6, 1998 Dedicated and automated system Rapid response utilizing GCN Wide field-of-view system to cover error box of early time notice Experimental Goal & Method LOTIS at LLNL GRB satellites LOTIS GCN GROCSE/LOTIS attempts to detect optical radiation simultaneously with the  -ray bursts to understand  -ray burst production environment

3. 23 CCD cameras 60 deg FOV <20 sec response f/2.8, 250 mm f.l. 89 mm aperture 23 CCD cameras resolution: 1.2”/pxl Follow-up system for CGRO/BATSE and IPN error box GROCSE: Operated between Jan. ‘94~Jun. ‘96 Results: V=7.0 ~ 8.3 limits  best at that time BASTE Light CurveGROCSE coverageVlim=7.4 30° 68 mVmV 75 H.S. Park et al. ApJ 490, 99 (1997) GRB951117 Vlim=8.1 Vlim=8.3 GRB951124 GRB951220

4. LOTIS GRB Counterpart Search Experiments Follow-up system for CGRO/BATSE (Oct ’96~Mar ’02) - 17.6 x 17.6 deg Total FOV - Canon Telephoto f/1.8 lenses (200 mm focal length, 11 cm aperture) - 4 of 2048 x 2048 CCD cameras - Rapidly slewing mount - Weather-proof clam shell housing - Weather station - Limiting mV ~ 15 - GRB response time: < 5 sec - Simultaneous  to optical flux ratios - Site: LLNL’s test site in California - Operation: Oct ‘96 ~ Mar ‘02 - 100% automated system

5. LOTIS observation of GRB971227 (10 sec after burst) GRB971227 Cala Alto 2.2 m telescope image; 24 hrs later; J-Band BeppoSAX 1.5 arcmin error circle mV=12.3 LOTIS Image; 10 sec after mV=10.1  LOTIS obtained 500 images of the X-ray afterglow area from 10 sec to 6 hours; Quasi-simultaneous (10 sec after the burst) limit ~ mV=12.3 (GCNC #19)

6. Prompt Optical Upper Limits ? GRB 990123 see also: Tarot, ROTSE III, RAPTOR, RIKEN, BART, BOOTES,… see also: Tarot, ROTSE III, RAPTOR, RIKEN, BART, BOOTES,…

7. Super-LOTIS for HETE era Super-LOTIS - Follow-up observations for HETE2, Swift, Integral missions - 0.6 meter aperture: Boller-Chivens telescope -< 20 sec response time : light curve measurement from 30 sec to 4 hours - 2048 x 2048 CCD on prime focus - 0.8 x 0.8 deg FOV (1.5 arcsec/pixel) - Sensitivity: mV= 17 ~ 21 - V,R,I,Clear filter wheel -Moved to Kitt Peak in April 2000 -First HETE real-time trigger available May 2002 S-LOTIS WYN Solar Observatory Space Watch Kitt Peak, Arizona (USA)

8. GRB010921- Super-LOTIS afterglow observation 2.5’ Super-LOTIS: T0+21.8 hr Super-LOTIS: T0+25.2 hr Super-LOTIS: T0+45.8 hr Super-LOTIS: T0+49.2 hr DSS Image DPOSS R Image http://www.srl.caltech.edu/~react/fits/GRB010921f.fits 2.5’ N E Super-LOTIS detected GRB010921 afterglow 21.8 hours after the burst. The measured afterglow intensities are: V=19.4 ± 0.2.

9. GRB010921 light curve H. S. Park et al, GCN 1131; ApJ 571, L131 LOTIS data shows that the power-law decay curve for the afterglow cannot be extended to the early time.

10. Super-LOTIS Results GRB 010220 GRB 001025B (short/hard) t obs = 30.0 hrs; R > 18.9 GCN 873; ApJ 567,447 t obs = 7.2 hrs; R > 20.2 GCN 981 t obs = 23.7 hrs R = 20.0 GRB 010222 GRB 020531 t obs = 3.6 hrs; R > 17.5 GCN 1404 t obs = 21.8 hrs; R = 19.4 GCN 1131; ApJ 571, L131 GRB 010921 (HETE-2) t obs = 106 min.; R = 18.4 GCN 1492 GRB 020813 t obs = 14.0 hrs; R = 19.1 GRB 021004 t obs = 143 sec; R = 15.2 GCN 1736 GRB 021211

11. GRB971227 by LOTIS: 10 sec – no optical flash (Williams et al., ApJ 519, L25, 1998) GRB990123 by ROTSE: 22 sec (Akerlof et al., Nature, 398, 400, 1999) GRB021004 by RIKEN: 326 sec (Fox et al., Nature, 422, 284, 2003) GRB021211 by Super-LOTIS, KAIT, RAPTOR: 65 sec (Li et al., ApJ 586, L9, 2003) Prompt measurements are still very rare Requires real-time triggers, automatic system, many longitude coverage Time after GRB(days) R GRB990123 1 0.10.010.001 10 Time after GRB (days) 10 14 18 22 R GRB021004 Time after GRB(days) Mag GRB021211

12. SWIFT mission to solve GRB mysteries Science Instruments —BAT: CZT detector –50 to 300 keV —XRT: X-ray telescope – 0.2 to 10 keV —UVOT: CCD camera –170 to 650 nm Event Rate: 150 GRBs/year Real-time notice through GCN To be launched in May 2004 No Prompt Infrared or Spectroscopy on SWIFT! BAT UVOT XRT Spacecraft

13. Motivation for NIR Capability 1. Study the intrinsic NIR emission; prompt and afterglow (no Swift NIR) 2. Detect and observe optically obscured bursts; star forming regions 3. Detect and observe high redshift GRBs; Ly- α absorption GRB 970228, t = 1 day Lamb & Reichart ApJ 536, 1 see also: Ciardi & Loeb ApJ 540, 687 Inque et al. Gou et al. Band (  m)  (  m) U0.3650.44 B0.440.098 V0.550.089 R0.700.22 I0.900.24 J1.250.3 H1.650.4 K2.20.6 L3.61.2 M4.80.8 N10.2

14. S-LOTIS Prompt NIR and Optical GRB Counterpart Searches invar spider frame coma corrector focus stage mount motor drives CCD camera filter wheel invar spider frame secondary mirror CCD camera focus stage IR camera dichroic beam splitter Current systemPlanned upgrade system Focal plane upgrade to install a CCD camera AND an NIR camera Secondary optics to produce f/9 system Beam splitting between optical and NIR bands Utilize already existing Super-LOTIS optics, mount, control system NIROptical Pixel sizes 40  m x 40  m13  m x 13  m Plate Scale1.5 arcsec/pxl0.5 arcsec/pxl Total pxls256 x 2562048 x 2048 FOV6.4 arcmin x 6.4 arcmin17 arcmin x 17 arcmin FiltersJ,H,K,KsB,V,R,I

15. Super-LOTIS Upgrade Instrument Configuration Compensator/Dither Plate Dichroic Beam Splitter CIRIM NIR Camera Primary Mirror CCD Camera Optical Corrector NIR Filter Wheel NIR Relay Optics Cold Stop Optical Filter Wheel

16. Optical Elements CCDCorrectorFilter Optical PathNIR Path Beam Splitter NIR compensator Optical design completed; the elements are being fabricated by TORC

17. Spot Diagrams 20.0 μm 40.0 μm NIR Spots Optical Spots Optical performance matches the focal plane array pixel sizes

18. Optical CCD Camera Spectral Instruments CCD Camera CCD: EEV 42-40, thinned Pixels: 2048 x 2048, 13.5 μm Readout Rate: 100 – 800 kHz Read Noise: 5.59 e- @ 400 kHz Gain: 1.24 e-/ADU Operating Temperature: -35 ˚C Dark Current: < 0.07 e-/pix/s Full Well: 98.7 ke- Pixel Scale: 0.5”/pixel f/9 FOV: 17’ x 17’ Filter Wheel: BVRI Limiting Magnitude: R ~ 19.0

19. NIR Camera CIRIM: Cerro Tololo InfraRed IMager Readout Electronics: IR Labs (upgradable) Array: 256x256 Pixel HgCdTe NICMOS-3 Rockwell Pixel Size: 40 μm x 40 μm Operating Temperature: LN2 @ 77K Read Noise: ~ 50 e- Gain: ~ 4 e-/ADU Dark Current: < 2.5 e-/pix/s Full Well: 130 ke- Pixel Scale: 1.5”/pixel f/9 FOV: 6.5’ x 6.5’ (Swift BAT error box ~ 5’) Filter Wheel: JHK s K Limiting Magnitude: J = 16.0, H = 15.7, K = 15.3

20. Super-LOTIS NIR camera expected performance Assumptions: G-type star Atmospheric transmission Mirror reflectivity Transmission efficiency through filters HgCdTe array quantum efficiency Constant sky background Sensitivity @ 30 sec & SNR = 10 J = 16.5 H = 16.2 K = 15.8

21. Super-LOTIS Current Status Optical design completed (Nov. 2003) Concrete pier construction completed (Dec. 2003) Rechecking system (Jan 2004) Install new CCD camera (Feb 2004) NIR camera readout electronics (Will be completed by June 2004) NIR/Optical camera operation (Jul 2004)

22. Summary Early-time light curves are still mystery Simultaneous optical light curve measurement will provide clues to understand GRB’s progenitors and their environment We need many more prompt / simultaneous GRB counterpart detections Prompt IR follow-ups by upgraded S- LOTIS and REM will be important measurements for Swift http://slotis.kpno.noao.edu/LOTIS/index.shtml 1 0.10.010.001 10 Time after GRB (days) 10 14 18 22 R GRB021004 GRB970508