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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"

27261 results found.

  1. LIGO/Virgo G298048: H.E.S.S. very-high energy gamma-ray follow-up
  2. LIGO/Virgo G297595: H.E.S.S. very-high energy gamma-ray follow-up
  3. LIGO/Virgo G298048: INTEGRAL pointed follow-up observations
  4. LIGO/Virgo G298389: CALET Observations
  5. LIGO/Virgo G298936 : Fermi-LAT search for a high-energy gamma-ray counterpart
  6. GRB 170823A: Swift detection of a burst
  7. LIGO/Virgo G298936: Swift/BAT data search
  8. LIGO/VIRGO G298936: Fermi GBM Observations
  9. LIGO/Virgo G298936: AGILE MCAL observations
  10. LIGO/Virgo G298936: INTEGRAL was inactive at the time of the event
  11. LIGO/Virgo G298936: IceCube neutrino observations
  12. GRB 170822A: RATIR Optical and NIR Observations
  13. GRB 170822A: Swift-BAT refined analysis
  14. GRB 170822A: Swift/UVOT Upper Limits
  15. LIGO/Virgo G298048: Chandra X-ray observations
  16. GRB 170822A: Swift-XRT refined Analysis
  17. LIGO/Virgo G298389 : MAXI/GSC observations
  18. LIGO/Virgo G298048: observations of optical counterpart candidate with CHILESCOPE observatory
  19. GRB 170822A:BOOTES-5/JGT optical afterglow candidate
  20. LIGO/Virgo G298048: CALET Observations
  21. GRB 170822A: Swift detection of a burst
  22. LIGO/Virgo G298048: observations of optical counterpart candidate with CHILESCOPE observatory
  23. LIGO/Virgo G298048: Continued monitoring of the optical counterpart candidate
  24. Konus-Wind observation of GRB 170816A
  25. LIGO/Virgo G298389: Swift/BAT data search
  26. LIGO/Virgo G298048: optical observations of CHILESCOPE observatory
  27. LIGO/Virgo G298389 : Fermi-LAT search for a high-energy gamma-ray counterpart
  28. GRB 170816A CALET Gamma-Ray Burst Monitor detection
  29. LIGO/Virgo G298048: Possible X-ray detection with Swift
  30. LIGO/Virgo G298389: INTEGRAL search for a prompt gamma-ray counterpart
  31. LIGO/Virgo G298048: GROND observations of candidate optical counterpart
  32. LIGO/Virgo G298389: Fermi GBM Upper Limits
  33. LIGO/Virgo G298048: Continued observation for DLT17ck
  34. LIGO/Virgo G298389: AGILE GRID observations
  35. LIGO/Virgo G298389: IceCube neutrino observations
  36. LIGO/VIRGO G298048: INAF VST-ESO PARANAL observations
  37. LIGO/Virgo G298048: further REM optical/NIR observations of candidate in NGC 4993
  38. GRB 170817B: Insight-HXMT observation
  39. LIGO/Virgo G298048: Further VLA Observations
  40. LIGO/Virgo G298048: GROND photometry of candidate optical counterpart reveals brightening in the NIR
  41. GRB 170818A: Fermi GBM detection
  42. LIGO/Virgo G298048: Archival VLA observations
  43. LIGO/Virgo G298048: ASKAP search for fast radio bursts
  44. LIGO/Virgo G298048: SkyMapper uvgri photometry of the candidate in NGC 4933
  45. LIGO/Virgo G298048: Likelihood of SSS17a Being an Unrelated Extragalactic Transient in NGC 4993
  46. LIGO/Virgo G298048: REM optical/NIR observations
  47. LIGO/Virgo G298048, Fermi GBM trigger 524666471/170817.529: MAXI/GSC observations
  48. LIGO/VIRGO G298048: Swift UVOT detection and XRT upper limits
  49. LIGO/VIRGO G298048: Magellan Optical Spectrum of the Potential Optical Counterpart Associated with NGC 4993
  50. LIGO/Virgo G298048: VLA Detection
  51. LIGO/Virgo G298048: Galaxy-Targeted Optical Followup With Las Cumbres Observatory
  52. LIGO/VIRGO G298048: The Potential Optical Counterpart in NGC 4993 Has Afterglow-Like Colors
  53. GRB 170817B: Fermi GBM detection
  54. LIGO/Virgo G298048: DLT40 follow-up observation
  55. LIGO/Virgo G298048: Inspection of archival HST data at the position of the potential optical counterpart
  56. LIGO/Virgo G298048: Nearby Galaxies in the Localization Volume using the updated sky map computed using LALInference
  57. LIGO/Virgo G298048 : Fermi-LAT search for a high-energy gamma-ray counterpart
  58. LIGO/Virgo G298048: Optical Candidate Shows No Evidence for Previous Activity in Archival ASAS-SN Data
  59. LIGO/Virgo G298048: REM optical/NIR observations of candidate in NGC 4993
  60. LIGO/Virgo G298048: Potential optical counterpart discovered by Swope telescope
  61. LIGO/Virgo G298048 - Update on Fermi/GBM GRB 170817A Analysis
  62. LIGO/Virgo G298048: AGILE GRID observations
  63. LIGO/Virgo G298048: AGILE MCAL observations
  64. LIGO/Virgo G298048: Swift/BAT data search
  65. LIGO/Virgo G297595: Pierre Auger Observatory neutrino follow-up
  66. LIGO/Virgo G298048: Nearby Galaxies in the Localization Volume with Face-on Assumption
  67. GRB 170817A: Fermi GBM detection
  68. LIGO/Virgo G298048: Nearby Galaxies in the Localization Volume
  69. LIGO/Virgo G298048: Insight-HXMT observations
  70. LIGO/Virgo G298048: Potential host galaxies from the GLADE catalog
  71. LIGO/Virgo G298048: IPN triangulation of Fermi/GBM trigger 524666471/170817529
  72. LIGO/Virgo G298048: Astrosat CZTI upper limits
  73. LIGO/Virgo G298048: Further analysis of a binary neutron star candidate with updated sky localization
  74. LIGO/Virgo G298048: COINCIDENT IceCube neutrino candidate with Fermi GBM trigger 524666471/170817529
  75. LIGO/Virgo G298048: Identification of a binary neutron star candidate coincident with Fermi GBM trigger 524666471/170817529
  76. LIGO/Virgo G298048: FOUND COINCIDENT IceCube neutrino observation
  77. LIGO/Virgo G298048: INTEGRAL detection of a prompt gamma-ray counterpart
  78. LIGO/Virgo G298048: Fermi GBM trigger 170817.529 and LIGO single IFO trigger
  79. LIGO/Virgo G298048: Fermi GBM trigger 524666471/170817529: LIGO/Virgo Identification of a possible gravitational-wave counterpart
  80. GRB 170816A: Fermi GBM detection
  81. LIGO/Virgo G297595: Swift-XRT sources
  82. GRB 170805A: AstroSat CZTI detection
  83. LIGO/Virgo G297595: INAF VST-ESO PARANAL observations
  84. LIGO/Virgo G296853: Pierre Auger Observatory neutrino follow-up
  85. LIGO/Virgo G297595: REM optical/NIR observations
  86. LIGO/Virgo G297595 : MAXI/GSC observations
  87. GRB 170813A: Fermi GBM observation
  88. Fermi GBM trigger 524493492/170815526 is not a GRB
  89. LIGO/Virgo G297595: Insight-HXMT observations
  90. LIGO/Virgo G297595: Nearby Galaxies in the Localization Volume
  91. LIGO/Virgo G297595: Fermi GBM Observations
  92. LIGO/Virgo G297595: Swift/BAT data search
  93. LIGO/Virgo G297595: AGILE GRID observations
  94. LIGO/Virgo G297595 : Fermi-LAT search for high-energy gamma-ray counterpart
  95. GRB 170813A: Swift/UVOT Upper Limits
  96. LIGO/Virgo G297595: INTEGRAL search for a prompt gamma-ray counterpart
  97. LIGO/Virgo G297595: SPI-ACS/INTEGRAL data investigations
  98. LIGO/Virgo G297595: IceCube neutrino observations
  99. GRB 170813A: Swift-BAT refined analysis
  100. GRB 170813A: RATIR Optical and NIR Observations

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