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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').
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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"

6803 results found.

  1. IceCube-191001A: HAWC follow-up
  2. Fermi-LAT Gamma-ray Observations of IceCube-191001A
  3. LIGO/Virgo S190930t: HCT observations of ZTF19acbpsuf
  4. LIGO/Virgo S190930t: Lulin Follow-up Observations of AT2019rpn and AT2019rpj
  5. IceCube-191001A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  6. LIGO/Virgo S190923y: optical spectrum of MASTER detected transient
  7. LIGO/Virgo S190930t: Transient found in Swift/UVOT counterpart search
  8. LIGO/Virgo S190930t: No counterpart candidates in Fermi-LAT observations
  9. LIGO/Virgo S190930s: No counterpart candidates in Fermi-LAT observations
  10. LIGO/Virgo S190930t: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  11. LIGO/Virgo S190930s: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  12. GRB 190926A: Swift-XRT refined Analysis
  13. LIGO/Virgo S190924h: No counterpart candidates in Fermi-LAT observations
  14. LIGO/Virgo S190924h: no counterpart candidates in AGILE-GRID observations
  15. Fermi-LAT Gamma-ray Observations of IceCube-190922B
  16. LIGO/Virgo S190924h: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  17. LIGO/Virgo S190923y: No counterpart candidates in Fermi-LAT observations
  18. Fermi-LAT Gamma-ray Observations of IceCube-190922A
  19. IceCube-190922B - HAWC follow-up
  20. LIGO/Virgo S190923y: INTEGRAL IBIS coded-masked imaging observations of part of the localization area and further all-sky upper limits
  21. LIGO/Virgo S190923y: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  22. IceCube-190922A - HAWC follow-up
  23. IceCube-190922A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  24. GRB 190919B: Swift-XRT observations
  25. GRB 190919B: GROND detection of the NIR afterglow
  26. HAWC-190916A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  27. Alert from the HAWC Burst Monitor HAWC-190917A
  28. LIGO/Virgo S190915ak: No counterpart candidates in Fermi-LAT observations
  29. LIGO/Virgo S190915ak: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  30. LIGO/Virgo S190910h: No counterpart candidates in Fermi-LAT observations
  31. LIGO/Virgo S190910d: No counterpart candidates in Fermi-LAT observations
  32. LIGO/Virgo S190910h: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  33. LIGO/Virgo S190910d: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  34. GRB 190823A: Swift-XRT afterglow detection
  35. GRB 190903A: Fermi GBM detection
  36. Chandra observations of GW170817 ~740-743 days since merger
  37. LIGO/Virgo S190901ap: No counterpart candidates in Fermi-LAT observations
  38. LIGO/Virgo S190901ap: No counterpart candidates in INTEGRAL SPI-ACS,prompt observation
  39. GRB 190829A: TNG imaging of the NIR afterglow
  40. GRB 190829A: Fermi GBM detection
  41. GRB 190829A: Fermi-LAT Upper Limits
  42. GRB 190829A: GROND detection of the Optical/NIR Afterglow
  43. GRB 190829A: Swift-XRT refined Analysis
  44. GRB 190828B: Swift-XRT refined Analysis
  45. GRB 190828A: Swift-XRT observations
  46. LIGO/Virgo S190828l: No counterpart candidates in Fermi-LAT observations
  47. GRB 190828B: Fermi GBM observation
  48. LIGO/Virgo S190828j: No counterpart candidates in Fermi-LAT observations
  49. LIGO/Virgo S190814bv: no variation of DESGW candidates AT 2019onj and AT 2019okr from ENGRAVE VLT/HAWK-I observations, and archival detection
  50. LIGO/Virgo S190828l: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  51. LIGO/Virgo S190828j: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  52. LIGO/Virgo S190814bv: SALT optical spectrum of candidate DG19aqbkc
  53. LIGO/Virgo S190814bv: LCO Photometry of DG19wxnjc/AT2019npv
  54. GRB 190823A: Swift-XRT observations
  55. GRB 190816A: Swift-XRT afterglow detection
  56. GRB 190824A: Swift-XRT refined Analysis
  57. GRB 190824A: Fermi GBM observation
  58. LIGO/Virgo S190814bv: GROND follow-up observations of AT2019npv
  59. LIGO/Virgo S190814bv: ENGRAVE VLT/HAWK-I observations and archival detection of the CFHT candidate
  60. GRB 190821A: Swift-XRT refined Analysis
  61. GRB 190821A: Fermi GBM observation
  62. Fermi GBM-190816: No counterpart candidates in Fermi-LAT observations
  63. Fermi-LAT Gamma-ray Observations of IceCube-190819A
  64. IceCube-190819A - HAWC follow-up
  65. Fermi GBM-190816: Location-dependent upper limits from INTEGRAL/SPI-ACS prompt observation
  66. IceCube-190819A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  67. LIGO/Virgo S190814bv: No strong counterpart candidates in Swift/XRT observations
  68. GRB 190816A: Swift-XRT observations
  69. LIGO/Virgo S190814bv: Fermi-LAT search for a high-energy gamma-ray counterpart
  70. LIGO/Virgo S190814bv: GRAWITA TNG infrared imaging of desgw-190814e, DG19sevhc and selected galaxies
  71. LIGO/Virgo S190814bv: Konus-Wind observations
  72. LIGO/Virgo S190814bv: GRAWITA TNG infrared imaging of selected galaxies
  73. LIGO/Virgo S190814bv: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  74. HAWC-190806A: upper limits from INTEGRAL SPI-ACS and IBIS prompt observation
  75. HAWC-190806A: Swift-XRT observations
  76. HAWC Burst Alert 1008846_957: Konus-Wind observations
  77. GRB 190804B: Swift-XRT afterglow detection
  78. Alert from the HAWC Burst Monitor
  79. GRB 190805B: Swift-XRT observations
  80. GRB 190805B: Fermi GBM detection
  81. GRB 190804B: Swift-XRT observations
  82. GRB 190731A: Swift-XRT afterglow detection
  83. GRB 190731A: Fermi GBM detection
  84. GRB190731A: Fermi-LAT detection
  85. Fermi-LAT Gamma-ray Observations of IceCube-190730A
  86. IceCube-190730A - HAWC follow-up
  87. IceCube 190730A: one weakly associated counterpart candidates in INTEGRAL SPI-ACS, and IBIS prompt observation
  88. LIGO/Virgo S190728q: No counterpart candidates in Fermi-LAT observations
  89. LIGO/Virgo S190728q: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  90. GRB 190727B: Fermi-LAT detection
  91. GRB 190727B: Fermi GBM observations
  92. LIGO/Virgo S190727h: No counterpart candidates in Fermi-LAT observations
  93. LIGO/Virgo S190727h: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  94. LIGO/Virgo S190718y: Swift XRT observations, 45 X-ray sources
  95. LIGO/Virgo S190720a: No counterpart candidates in Fermi-LAT observations
  96. GRB 190720A: Fermi GBM detection
  97. GRB 190719C: Fermi GBM detection
  98. GRB 190719C: Swift-XRT refined Analysis
  99. LIGO/Virgo S190720a: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  100. GRB 190719C: NOT candidate optical afterglow and host

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