for Lomonosov-GRB collaboration Results of the Multimessenger GRB Observations in the Lomonosov Mission Vitaly Bogomolov, for Lomonosov-GRB collaboration

“LOMONOSOV” SPACE MISSION Was launched 28/04/2016 Scientific objectives: Study of ultra-high energy cosmic rays phenomena in hard x-rays and soft gamma-rays (0.01-3.0 MeV) Search and detection of optical transients accompanying gamma-ray bursts study of transient luminosity events in the Earth atmosphere magnetosphere physics research

Parameters of “Lomonosov” mission: Orbit: ~500 km, polar Mass: spacecraft ~600kg, payload ~150kg Total power ~ 300W Data amount ~3Gb/day Launch date – 28/04/2016 Complex of instruments: BDRG – gamma spectrometer SHOK – wide field optical camera UFFO – coding mask x-ray telescope + UV telescope TUS – Telescope for detecting flashes in atmosphere produced by cosmic rays with E>5*10^19 eV and TLEs DEPRON, ELFIN-L – particle detectors

Instrument BDRG onboard “Lomonosov” BDRG instrument consists of 3 similar detector boxes, connected to data analysis box. Parameters of each BDRG box: Detector: 3mm NaI(Tl) /17 mm CsI(Tl) Sensitive area: 130mm Energy range: 0.01 – 3 MeV Sensitivity for GRBs 10-7 erg/sm2 GRB localization- ~2о for bright GRBs Goals of BDRG: 1. Production of GRB trigger 2. Spectral measurements and timing of GRB in hard x-ray and gamma range 3. Estimation of GRB coordinates 4. X-ray and gamma-ray monitoring 5. Study of TGFs

Structure and amount of information from BDRG 3 detector boxes Type of frame Time interval between frames Data amount, Mb Continuous (180 Mb per day) Monitoring 100ms 87 per day Spectrum 15s 48 per day Event mode 50 per day Burst mode for fast/slow burst (5 Mb per burst) 1-10 ms 1.6 per burst 1-10 s   Not regular, up to 106 events The day portion of BDRG data is about 500-1000 Mb

Parameters of SHOK optical cameras for “Lomonosov” space mission Two identical SHOK boxes with wide-field cameras and processor unit for image analysis are used. Each SHOK unit is a fast-acting wide-angle camera, which provide recording of optical emission with maximum magnitude of 9−10m at a single frame and exposure time of 0.2 seconds Parameters of each SHOK box: FOV: 20o x 40o Time resolution: 0.2s Sensitivity: 10 st. mag (in 200ms frame) Mass ~5kg Power ~27W (used by camera and powerful internal processor) Photo of optical camera used in SHOK instrument

Data from SHOK optical cameras transferred to ground Two kinds of data are collected For each GRB pictures taken from ~1min before trigger to ~2 min after trigger with time interval 0.2s are transferred (total FOV frames). Amount of data is ~700Mb per GRB Between GRB triggers the difference between neighbor frames will be analyzed and parts of FOV (several degrees) with most significant changes are transferred. Most of such events are expected to be connected with some near Earth objects.

Production of GRB trigger Several time scales for independent triggering: 10 ms interval, 1 ms resolution of transmitted data (“Fast”) 1 s interval, 10 ms resolution of transmitted data (“Slow”) 20 s interval, enlarged event mode transmitted data (“SuperSlow”) 2-Levels of trigger Internal trigger: only BDRG data fixation Alert trigger: Trigger for ShOK and messages via GlobalStar modem Main mode: BDRG1  SHOK1 (any or if source in camera FOV) BDRG2  SHOK2 (any or if source in camera FOV) Redundant mode: BDRG1  SHOK1, SHOK2 BDRG2  SHOK1, SHOK2 BDRG3  SHOK1, SHOK2 System is operating this way

BDRG background conditions for GRB triggering

GRB catalog N GRB date GRB time GRB name Duration, s detectors Most illuminated BDRG triggers Range, keV GCN circulars 1 07.06.2016 11:13:56 GRB160607A 10 100 - 100-170 2 03.07.2016 12:10:02 GRB160703A 42 010 10-300 19725 3 05.07.2016 17:40:19   011 30-300 4 20.07.2016 18:23:55 GRB160720A 87 01X slow, sslow 10-800 19728 5 02.08.2016 6:13:30 GRB160802A 20 slow 20-300 19759 6 14.08.2016 21:12:42 GRB160814A 70 X11 20-170 7 24.08.2016 14:21:07 GRB160824B 111 250-1000 19884 8 08.09.2016 5:17:06 GRB160908A 30 X1X 10-170 9 11.09.2016 14:07:55 11X 100-500 12.09.2016 8:24:09 21 10X 60-900 11 15.09.2016 22:51:12 12 101 120-1000 19989 17.09.2016 10:56:12 sslow 200-1600 19992 13 11:30:20 GRB160917A 25 70-1000 19990 14 15.10.2016 17:03:06 GRB161015A 15 130 - 1100 17.10.2016 17:52:17 GRB161017A 110 20075 16 06.11.2016 11:57:55 GRB 161106A 340-1100 20154 17 09.11.2016 6:11:45 GRB 161109A 35-300 20165 18 01.01.2017 2:26:12 GRB 170101А 20359 19 2:47:22 GRB 170101В 20360

Statistics of GRBs observed by BDRG/Lomonosov Probability to detect a GRB listed in GCN is ~20% (taking into account shadowing by the Earth and excluding the RB regions) Probability to detect a GRB not listed in GCN is less than 10%

Example of GRB observed near RB in the equator region

GRB161017A BDRG-2 NaI(Tl) counting rate time profiles in 15-600 keV energy range with different time resolution. The top panel is the light curve fragment with 100 ms time resolution. The middle panel is the detailed light curve around the most intensive peak (corresponding time interval is marked by red line on the top panel). The bottom panel is the light curve with 10 ms time resolution in the interval marked by red line on the middle panel, t-t0 means the time after trigger

Robotic telescope network MASTER (from SAI MSU)

17:55:38 --- Detection of OT at 4 pare pf frames, OT confirmation 17:54:01 --- forth image (30) 17:54:49 --- detection of OT at 3 pare of frames 17:52:16 --- notice to telescopes 17:52:38 --- first observation MASTER-Amur (10s) 17:53:02 --- second image MASTER-Amur (10s) 17:51:51 --- Swift trigger 17:53:27 --- third image (20) 17:55:48 --- notice to GCN from MASTER 18:04:12 --- notice to GCN from Swift 0 25 47 71 96 130 178 227 237

GRB 161017A observations by Lomonosov/BDRG and MASTER

Common Lomonosov, MASTER-net and Swift observations of GRB 161017A in broad bads from optics to gamma: light curve

Energy spectrum of GRB 161017A in broad bads from optics to gamma observed by Lomonosov, MASTER-net and Swift

Thank You!

Accuracy of GRB localization from BDRG data Standard formula for cosine shape of FOV: Here cos 1 ,, cos 2 and cos 3 are cosines of the angles between the axis of correspondent BDRG box and the GRB direction. Result of laboratory test with 241Am source Dependence on fluence, kT and background rate (the results of Geant numeric modeling) Slow GRB triggers (20s time of analysis) were produced by fast placing of 241Am ~130 cm above BDRG detectors and ~53 cm far from axis of the system. Count rate from the source was approximately equal to background one in the 25-100 keV channel chosen for GRB triggering (~30 s-1 for each detector)

Problem of GRB triggering on low polar orbit: triggering on electron precipitations

BDRG: examples of light curves