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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"

28262 results found.

  1. EP240802a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  2. GRB 240802A: AstroSat CZTI detection of a long burst
  3. EP240801a: further SAO RAS optical observations
  4. EP240801a: optical observations at CrAO and AbAO
  5. EP240801a: Leavitt Observatory optical observations
  6. EP240801a: SAO RAS optical observations
  7. EP240801a: JinShan optical observations
  8. GRB 240727C: SVOM/GRM observation
  9. EP240801a: follow-up observation with LCOGT
  10. Fermi GBM trigger 744179961 / 240801194 can not be confirmed as a GRB
  11. GRB 240730A: Swift-BAT refined analysis
  12. EP240801a: GSP follow-up observations of the candidate counterpart
  13. EP240801a: Kinder follow-up observations of the candidate counterpart
  14. EP240801a: GMG observation
  15. EP240801a: TRT optical counterpart detection
  16. EP240801a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  17. GRB 240801B: AstroSat CZTI detection of a bright long burst
  18. GRB 240801A: Fermi GBM Final Real-time Localization
  19. GRB 240730C: AstroSat CZTI detection of a long burst
  20. GRB 240730A: Osservatorio Astronomico Nastro Verde upper limit
  21. GRB240730A: BOOTES-5/JGT early optical upper limit
  22. Swift GRB 240730A: Global MASTER-Net observations report
  23. GRB 240730A: Swift-XRT refined Analysis
  24. GRB 240715A: Swift-XRT afterglow detection
  25. GRB 240730A: Swift/UVOT Upper Limits
  26. GRB 240730A: Enhanced Swift-XRT position
  27. GRB 240730A: Swift detection of a burst
  28. GRB 240727A: Swift-BAT refined analysis
  29. LIGO/Virgo/KAGRA S240615dg: GRAWITA wide-field optical observations
  30. GRB 240727A: observations of optical counterpart.
  31. GRB 240727B: Swift-XRT observations
  32. Fermi GRB 240727A: Global MASTER-Net observations report
  33. GRB 240727A: Swift/UVOT detection
  34. GRB 240727A: Osservatorio Astronomico Nastro Verde upper limit
  35. GRB 240727A: NOT optical observation
  36. GRB 240727A: JinShan optical upper limits
  37. GRB 240727A Bassano Bresciano Observatory upper limit
  38. GRB 240727C: AstroSat CZTI detection of a long burst
  39. GRB 240727A: Swift-XRT refined Analysis
  40. Fermi GRB 240726A: Global MASTER-Net observations report
  41. GRB 240727A: Enhanced Swift-XRT position
  42. GRB 240727B: Fermi GBM Observation
  43. GRB240529A: VIRT optical transient detection
  44. GRB 240727B: Swift/BAT-GUANO arcminute localization of a long burst
  45. GRB 240726A: SVOM/GRM observation
  46. GRB 240726B: AstroSat CZTI detection of a short burst
  47. GRB240727A: Skynet Optical Afterglow Observations
  48. GRB 240727A: TRT optical afterglow detection
  49. GRB 240727A: Swift detection of a burst
  50. IceCube-240725A: Upper limits from a search for additional neutrino events in IceCube
  51. Fermi-LAT gamma-ray observations of IceCube-240725A
  52. Swift Trigger 1244778 is not a GRB
  53. IceCube-240721A: Two candidates from the Zwicky Transient Facility
  54. GRB 240720A: Swift-BAT refined analysis
  55. IceCube-240721A: Upper limits from a search for additional neutrino events in IceCube
  56. LIGO/Virgo/KAGRA S240716b: Upper limits from Swift/BAT-GUANO
  57. LIGO/Virgo/KAGRA S240703ad: Upper limits from Swift/BAT-GUANO
  58. Fermi-LAT gamma-ray observations of IceCube-240721A
  59. GRB 240720B: SVOM/GRM observation
  60. GRB 240720B: AstroSat CZTI detection of a short burst
  61. GRB 240718A: Fermi GBM Observation
  62. GRB 240718A: SVOM/GRM observation
  63. GRB 240718A: BALROG localization (Fermi Trigger 742976945 / GRB 240718270)
  64. GRB 240712A: Swift-BAT refined analysis
  65. GRB 240716A: GECAM-B detection of a long burst
  66. IceCube-Cascade 240714A: X-ray follow-up observation with EP-FXT
  67. Fermi-LAT gamma-ray observations of IceCube-cascade-240714A
  68. GRB 240715A: Swift/UVOT observations of the XRT sources.
  69. GRB 240715A: Swift-XRT observations
  70. GRB240713A: Swift/UVOT Upper LImits
  71. EP240708a: X-ray follow-up observations with Swift/XRT
  72. LIGO/Virgo/KAGRA S240716b: Updated Sky localization
  73. GRB 240713A: Swift-XRT observations
  74. GRB 240715A: TRT optical upper limit on one Swift/XRT candidate
  75. GRB 240712A: Swift-XRT refined Analysis
  76. GRB 240713A: LAST optical upper limit
  77. LIGO/Virgo/KAGRA S240716b: Identification of a GW compact binary merger candidate
  78. Fermi GRB 240715A: Global MASTER-Net observations report
  79. GRB 240713A: optical upper limits from the INAF Asiago Observatory
  80. GRB240715A: GRANDMA Optical Upper Limits
  81. GW s240422ed: Swift UVOT follow-up
  82. GRB 240712A: Swift/UVOT Upper Limits
  83. JinShan confirmation of the EP-WXT source triggered on July 14th due to a flaring star
  84. The EP-WXT source triggered on July 14th is likely a flaring star
  85. GRB 240713A: J-band upper limit from WINTER
  86. GRB 240713A: NOT optical upper limits on three EP/FXT candidates
  87. GRB 240713A: JinShan optical upper limits
  88. GRB 240713A: OHP/T120 optical upper limit
  89. GRB240713A: Optical upper limit with Kinder observations
  90. Fermi Sub-threshold Observation of GRB240713A
  91. GRB240713A : The first probable GRB Located on-Board SVOM by ECLAIRs
  92. EP240708a: GSP optical upper limit
  93. GRB 240712A: Swift detection of a burst
  94. LIGO/Virgo/KAGRA S240711cm: Coverage and upper limits from MAXI/GSC observations
  95. LIGO/Virgo/KAGRA S240627by: Updated Sky localization and EM Bright Classification
  96. Fermi GRB 240710A: Global MASTER-Net observations report
  97. EP240708a: NOT optical observations
  98. EP240708a: SVOM/C-GFT optical upper limit
  99. EP240708a: Optical upper limits with Kinder observations
  100. EP240708a: EP-WXT detection of a fast X-ray transient

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