1 / 18

G amma-ray L arge A rea S pace T elescope: Physics Goals and Instrument Status

Learn about the GLAST mission goals, instrument overview, international collaborations, scientific capabilities, and current status. Explore the physics objectives and key features of the Gamma-ray Large Area Space Telescope.

Download Presentation

G amma-ray L arge A rea S pace T elescope: Physics Goals and Instrument Status

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Gamma-ray Large Area Space Telescope: Physics Goals and Instrument Status LAT Jennifer Carson SLAC/KIPAC for the GLAST LAT collaboration GBM GLAST lifetime: 5+5 years Launch date: Fall 2007

  2. GLAST LAT Collaboration Principal Investigator: Peter Michelson (Stanford & SLAC) ~225 Members (~80 Affiliated Scientists, 23 Postdocs, and 32 Graduate Students) Cooperation between NASA and DOE, with key international contributions from France, Italy, Japan and Sweden. Managed at Stanford Linear Accelerator Center (SLAC). • France • IN2P3, CEA/Saclay • Italy • INFN, ASI • Japan • Hiroshima University • ISAS, RIKEN • Sweden • Royal Institute of Technology (KTH) • Stockholm University • United States • California State University at Sonoma • University of California at Santa Cruz - Santa Cruz Institute of Particle Physics • Goddard Space Flight Center – Laboratory for High Energy Astrophysics • Naval Research Laboratory • Ohio State University • Stanford University (SLAC and HEPL/Physics) • University of Washington • Washington University, St. Louis Jennifer Carson - GLAST

  3. GLAST Burst Monitor (GBM) PI: Dr. Charles Meegan (MSFC) NaI crystals (12) low-energy spectral coverage 8 keV to 1 MeV BGO crystals (2) high-energy spectral coverage 150 keV to 30 MeV GBM http://f64.nsstc.nasa.gov/gbm/ 8 keV < E < 30 MeV (overlaps w/ LAT) FoV = 9.5 sr 12% energy resolution at 511 keV On-board localization: < 15° in 1.8s 2-3° localization in ~10s – minutes ~200 GRBs/year, > 50 in LAT FoV Status: Being integrated onto spacecraft! Jennifer Carson - GLAST

  4. Large Area Telescope (LAT) ~20 MeV < E < ~300 GeV 2.4 sr FoV • Tracker (16 towers): • Facilitates pair conversion •  Tungsten conversion foils • Measures e-/e+ track •  18 layers of Si strips •  87 m2 of Si! Anti-coincidence detector: - Segmented - Vetos CR background Calorimeter: - Measures photon energy  1536 CsI crystals Jennifer Carson - GLAST

  5. Angular Resolution (per ) < 0.1° at E = 10 GeV < 0.35° at E = 1 GeV Effective Area 104 cm2 at 10 GeV LAT Features & Status Point-source sensitivity thick 1 year thin 5 years 3  10-9 cm-2 s-1 in 1 yr ~10,000 sources! Src loc.: ~0.4’ – 10’ http://www-glast.slac.stanford.edu/software/IS/glast_lat_performance.htm • Status: • - All vibration tests completed • Currently in thermal vacuum testing • - Detector response tests underway at CERN • - Ships for integration onto spacecraft: 9/15/06 all layers Jennifer Carson - GLAST

  6. Source Sensitivity: All-sky Scan Mode 100 seconds EGRET Fluxes • - GRB940217 (100sec) • - PKS 1622-287 flare • - 3C279 flare • - Vela Pulsar • - Crab Pulsar • - 3EG 2020+40 (SNR g Cygni?) • - 3EG 1835+59 • - 3C279 lowest 5s detection • - 3EG 1911-2000 (AGN) • - Mrk 421 • - Weakest 5 EGRET source 90 minutes (1 orbit) In 1 day, detect (at 5) the weakest EGRET sources. In 2 weeks, detect # of photons that EGRET detected in entire mission. Jennifer Carson - GLAST 1 day

  7. 55 Days of GLAST Science Catalogs Diffuse Emission AGN Pulsars & SNRs UIDs Galaxies Dark Matter GRBs Solar System Sources Realistic! Uncertainty in instrument response & background, + realistic science models Jennifer Carson - GLAST

  8. DC2 input model Likelihood output Monitoring Variability with GLAST • Input models: - broken PL - Flux / correlation - quiescence + moderate flare • Likelihood model: - single PL - daily averages during low/moderate flux levels Threshold for 1st year public data release (~2/month) Jennifer Carson - GLAST

  9. DC2 input model Likelihood output Monitoring Variability with GLAST Daily hardness ratios Jennifer Carson - GLAST

  10. DC2 input model Likelihood output Monitoring Variability with GLAST Twelve-hour exposures Jennifer Carson - GLAST

  11. DC2 input model Likelihood output Monitoring Variability with GLAST Six-hour exposures Jennifer Carson - GLAST

  12. Courtesy of J. Chiang X-ray LAT Snapshot SEDs with GLAST SED evolution w/ synch. cooling  Light curves on few-hour timescales  Rb/D  If cool ~ days (c.f. Böttcher & Chiang 2002)… - 12-hour exposures: F/F < 10%, / < 5%   track particle cooling after flares  measure  as e-s cool constrain B, 1, 2, p 12-hr exp  snapshot SEDs during cooling Expect dozens of srcs w/ these measurements Hardness ratios Twelve-hour exposures Jennifer Carson - GLAST

  13. Time-averaged SEDs: Past Efforts Petry et al. 2000 • Simultaneous Mrk 501 data (1997) - RXTE, BATSE, HEGRA - Two epochs (1 week each) • Non-simultaneous EGRET data • One-zone, time-ave. SSC model: magnetic field B  blob radius RB  e-distribution (ne, p, 1, 2) • Data cannot constrain B and 1 • Need complete, simultaneous HE coverage! Mrk 501 Low state High state Jennifer Carson - GLAST

  14. Time-averaged SEDs with GLAST Unbinned analysis Simulated data LAT VERITAS sensitivity Mrk 501 Jennifer Carson - GLAST

  15. Time-averaged SEDs with GLAST With joint LAT/TeV observations, cover the entire HE peak…  Constrain 1 & B Plus X-ray observations…  Probe relative contributions of Synch. & IC cooling  Measure all parameters: Rb, B, ne, p, 1, 2 Unbinned analysis BeppoSAX LAT VERITAS Mrk 501 Jennifer Carson - GLAST

  16. Summary • The instruments - GBM is undergoing integration with the spacecraft - LAT is completing thermal vacuum tests, spacecraft integration begins soon • The strategy - Survey mode  entire sky every three hours - Thousands of new sources expected! • Examples of the (AGN) science - Track variability on hourly timescales during bright states - Snapshot SEDs of bright flares - Daily averages during moderate and low states - Time-averaged SEDs during quiescence  Test emission models, measure physical parameters First GLAST Science Symposium: February 2007 at Stanford! Jennifer Carson - GLAST

  17. Backup Slides Jennifer Carson - GLAST

  18. Survey Mode: LAT Sensitivity & Exposure Point source sensitivity in survey mode Point source detection limit 100 seconds 90 minutes (1 orbit) 1 day Courtesy of J. McEnery Exposure comparison: Survey vs. pointed (position of Mrk 421) Exposure Pointed Survey Time (minutes) Time (minutes) Time (days) Pointed mode Survey mode Jennifer Carson - GLAST

More Related