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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

24576 results found.

  1. LIGO/Virgo G268556/GW170104: Lomonosov BDRG observations
  2. LIGO/Virgo G268556: Continued iPTF Observations and Additional Optical Transient Candidates
  3. LIGO/Virgo G268556: CALET Observations
  4. LIGO/Virgo G268556: iPTF Optical Transient Candidates
  5. Discovery Channel Telescope Imaging of ATLAS17aeu (LVCG268556)
  6. LIGO/Virgo G268556: AGILE-GRID preliminary analysis
  7. LIGO/Virgo G268556: Swift-XRT detection of ATLAS17aeu
  8. LIGO/Virgo G268556: Updated sky map from gravitational-wave data
  9. LIGO/Virgo G268556: HAWC follow-up of northern sky
  10. LIGO/Virgo G268556: Pan-STARRS1 observations of the skymap
  11. LIGO/Virgo G268556: ATLAS17aeu - an unusual transient within the skymap
  12. LIGO/Virgo G268556: ATLAS imaging of the skymap
  13. LIGO/Virgo G268556: DESGW/DECam observations
  14. LIGO/Virgo G268556: AGILE MCAL and Super-AGILE Observations
  15. LIGO/Virgo G268556: Fermi-LAT search for high-energy gamma-ray counterpart
  16. LIGO/Virgo G268556: Mini-MegaTORTORA follow-up observations
  17. LIGO/Virgo G211117 / GW151226: LOFAR follow-up
  18. LIGO/Virgo G268556: ANTARES search
  19. LIGO/Virgo G268556: observation regions by Project Mini-GWAC of SVOM
  20. GRB170104.78 MASTER-Net OT detection
  21. LIGO/Virgo G268556: INTEGRAL search of temporally coincident prompt hard X-ray emission
  22. LIGO/Virgo G268556: Fermi GBM Observations
  23. LIGO/Virgo G268556: Identification of a GW CBC Candidate
  24. Konus-Wind observation of GRB 170101A
  25. GRS 1716-249/GRO J1719-24/V2293 Oph, Swift-BAT refined analysis
  26. GRB 170101A: Swift-BAT refined analysis
  27. Trigger 729410: Swift detection of V2293 Oph
  28. GRB 170101B: Fermi GBM detection
  29. GRB 170101A: Swift detection of a burst
  30. GRB161219B - Anticipated hyperluminal evidence
  31. GRB 161214B: MASTER-Kislovodsk early optical observations
  32. GRB 161214A: MASTER-IAC early optical observations
  33. GRB 161224A: Swift-BAT refined analysis
  34. Trigger 728094, Swift-BAT refined analysis
  35. Swift Trigger 728268: a possible GRB
  36. Swift Trigger 728094: a possible GRB
  37. GRB161219.78 MASTER-Net OT detection
  38. GRB 161220A: Swift-BAT refined analysis
  39. Konus-Wind observation of GRB 161219B
  40. GRB 161219B: MITSuME Akeno Optical Observation
  41. GRB 161220A: GROND Upper Limits
  42. GRB 161219B: Swift-BAT refined analysis
  43. GRB 161219B: Watcher optical observations
  44. Konus-Wind observation of GRB 161218B
  45. IPN Triangulation of GRB 161218B (long/very bright)
  46. GRB 161220A: Swift detection of a burst
  47. GRB 161219B: LCO Sutherland observations
  48. GRB 161219B: GROND afterglow observations
  49. GRB 161219B: Swift-XRT refined Analysis
  50. GRB 161219A: a long GRB detected by INTEGRAL
  51. GRB 161218A: CALET Gamma-Ray Burst Monitor detection
  52. GRB 161218A: Swift-BAT refined analysis
  53. Konus-Wind observation of GRB 161218A
  54. Swift Trigger 727422 is not an astrophysical event.
  55. GRB 161218B: Fermi GBM detection
  56. GRB 161217A: MITSuME Okayama upper limits
  57. GRB 161217A: Swift-BAT refined analysis
  58. GRB 161218A: Swift detection of a burst
  59. GRB 161217A: Swift detection of a burst
  60. GRB 161214B: Swift-BAT refined analysis
  61. Fermi-LAT Gamma-ray Observations of IceCube-161210
  62. GRB 161214B: Swift-XRT refined Analysis
  63. GRB 161214B: NOT optical observations, possible counterpart
  64. GRB 161214B: Swift detection of a burst
  65. IceCube-161210: Konus-Wind upper limits
  66. GRB 161214A: GROND afterglow observations
  67. IceCube-161210: CALET Gamma-Ray Burst Monitor upper limits
  68. GRB 161214A: A long GRB detected by INTEGRAL
  69. HAWC follow-up on IceCube-161210
  70. INTEGRAL SPI-ACS and IBIS/Veto observation of IceCube-161210
  71. IceCube-161210: IceCube observation of a high-energy neutrino candidate event
  72. GRB 161129A: NOT optical observations and candidate host galaxy
  73. GRB 161129A: KWFC z-band photometry
  74. GRB 161203A: CALET Gamma-Ray Burst Monitor detection
  75. GRB 161206A: Fermi GBM detection
  76. Konus-Wind observation of GRB 161202A
  77. GRB 161202A: Swift-BAT refined analysis
  78. GRB 161202A: MITSuME Okayama upper limits
  79. GRB 161202A: Fermi-LAT detection
  80. GRB 161129A: MITSuME Okayama Ks-band Observation
  81. GRB 161129A: Swift-BAT refined analysis
  82. GRB 161129A: Fermi GBM Detection
  83. GRB 161129A: MITSuME Okayama Optical Observation
  84. GRB 161129A: Tautenburg Ic-band observations
  85. GRB 161129A: Swift-XRT refined Analysis
  86. GRB 161123A: Swift-XRT observations
  87. GRB 161117A: SMARTS optical/IR afterglow observations
  88. GRB 161119A: MASTER-SAAO possible OT detection during Fermi Alert
  89. Konus-Wind observation of GRB 161117A
  90. GRB 161117A: MASTER-OAFA (Argentina) prompt OT observations
  91. GRB 161117A: Fermi GBM detection/observation
  92. GRB 161117B: Swift-BAT refined analysis
  93. GRB 161117A: Swift-BAT refined analysis
  94. GRB 161117A: Swift-XRT refined Analysis
  95. GRB 161117B: LCO optical observations
  96. GRB 161117B: Swift detection of a burst
  97. GRB 161113A: Swift-BAT refined analysis
  98. GRB 161109A: CALET Gamma-Ray Burst Monitor detection
  99. GRB 161109A: Swift/UVOT Upper Limits
  100. GRB 161104A: Magellan imaging and spectroscopy

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