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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"

27294 results found.

  1. Fermi trigger No 736197684: Global MASTER-Net observations report
  2. GRB 240426A: VZLUSAT-2 detection
  3. GRB240430A: Fermi GBM Final Localization
  4. GRB 240501A: Fermi GBM Final Real-time Localization
  5. GRB 240408B: VZLUSAT-2 detection
  6. GRB 240407A: VZLUSAT-2 detection
  7. GRB 240429A: Fermi GBM Final Real-time Localization
  8. LIGO/Virgo/KAGRA S240422ed: GECKO/KMTNet ToO observations
  9. LIGO/Virgo/KAGRA S240429an: Retraction of GW compact binary merger candidate
  10. Fermi GRB 240428A: Global MASTER-Net observations report
  11. GRB 240428A: Fermi GBM Final Real-time Localization
  12. EP240426b: EP-WXT detection of a new fast X-ray transient
  13. LIGO/Virgo/KAGRA S240422ed: EP-FXT Detection of the Potential Opitcal Electromagnetic Counterpart AT 2024hfq Reported by DECam
  14. LIGO/Virgo/KAGRA S240422ed: EP-FXT detection of a candidate counterpart EP240426a
  15. LIGO/Virgo/KAGRA S240422ed: Zwicky Transient Facility contuinued observations of S240422ed and candidate analysis
  16. LIGO/Virgo/KAGRA S240422ed: 2.5m PRL Telescope follow-up of the Swift/XRT source S240422ed_X190
  17. LIGO/Virgo/KAGRA S240422ed: X-ray Upper Limits from EP-FXT for the Potential Electromagnetic Counterparts Reported by Swift and DECam
  18. LIGO/Virgo/KAGRA S240422ed: Upper limits from GECAM Observations
  19. LIGO/Virgo/KAGRA S240422ed: No significant candidates in GRANDMA and Kilonova-Catcher galaxy targeting observations
  20. GRB 240425A: Fermi GBM Final Real-time Localization
  21. Fermi trigger No 735697285: Global MASTER-Net observations report
  22. GRB 240419B: Swift-BAT refined analysis
  23. GRB 240421B: Swift-BAT refined analysis
  24. LIGO/Virgo/KAGRA S240422ed: Himalayan Chandra Telescope follow-up of the Swift/XRT source S240422ed_X101
  25. LIGO/Virgo/KAGRA S240422ed: No significant counterpart candidates in HAWC observations
  26. LIGO/Virgo/KAGRA S240422ed: No significant candidates in GRANDMA/FRAM Observations
  27. LIGO/Virgo/KAGRA S240422ed: X-ray Upper Limits from EP-WXT for the Potential Electromagnetic Counterparts Reported by Swift and DECam
  28. LIGO/Virgo S240422ed: Swift-XRT detection of 3 possible counterparts
  29. LIGO/Virgo/KAGRA S240422ed: Early X-ray Upper Limits from EP-WXT for the LVK Sky Localization Region
  30. LIGO/Virgo/KAGRA S240422ed: NOT J-band upper limit on the Swift/XRT source S240422ed_X61
  31. LIGO/Virgo/KAGRA S240422ed: X-ray Upper Limits from EP-WXT for the Three Potential Electromagnetic Counterparts Reported So Far
  32. GRB 240421B: GRBAlpha detection
  33. IceCube Alert 240424.08: Global MASTER-Net observations report
  34. LIGO/Virgo/KAGRA S240422ed: Potential Candidates from Magellan galaxy-based search
  35. LIGO/Virgo/KAGRA S240422ed: GOTO counterpart search
  36. GRB 240419A: Swift-BAT refined analysis
  37. GRB 240418A: Swift-BAT refined analysis
  38. LIGO/Virgo/KAGRA S240423br: Retraction of GW compact binary merger candidate
  39. LIGO/Virgo/KAGRA S240422ed: WINTER near-infrared J-band observations
  40. LIGO/Virgo S240422ed: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  41. LIGO/Virgo/KAGRA S240422ed: Zwicky Transient Facility observations and candidates
  42. LIGO/Virgo/KAGRA S240422ed: AstroSat CZTI non-detection and upper limits
  43. LIGO/Virgo/KAGRA S240422ed: Upper limits from Fermi-GBM Observations
  44. LIGO/Virgo/KAGRA S240421ar: Upper limits from Swift/BAT-GUANO
  45. LIGO/Virgo/KAGRA S240422ed: Coverage and upper limits from MAXI/GSC observations
  46. LIGO/Virgo/KAGRA S240422ed: Global MASTER-Net observations report
  47. Fermi trigger No 735470374: Global MASTER-Net observations report
  48. GRB 240414A: LBT optical detection
  49. GRB 240419B : MITSuME Akeno optical upper limits
  50. GRB 240415A: Swift-XRT refined Analysis
  51. Fermi GRB 240422A: Global MASTER-Net observations report
  52. GRB 240422A: Fermi GBM Final Real-time Localization
  53. GRB240421B: Zadko Observations
  54. Fermi GRB 240421B: Global MASTER-Net observations report
  55. Swift GRB 240421B: Global MASTER-Net observations report
  56. GRB 240421B: Fermi GBM Observation
  57. GRB 240421B: Swift-XRT refined Analysis
  58. GRB240421B: BOOTES-5/JGT optical upper limit
  59. GRB 240421B: J-band upper limits from WINTER
  60. GRB 240421B: Swift/UVOT Upper Limits
  61. Fermi GRB 240421A: Global MASTER-Net observations report
  62. EP240417a: no counterpart detection by SOAR
  63. EP240420a: Xinglong decaying optical counterpart
  64. GRB 240421B: Swift detection of a burst
  65. EP240420a: Nanshan optical counterpart observations
  66. GRB 240421A: Fermi GBM Final Real-time Localization
  67. EP240420a: detection of fading X-ray emission with refined position by EP-FXT
  68. EP240420a: NOT optical counterpart candidate and potential host
  69. Fermi trigger No 735280430: Global MASTER-Net observations report
  70. GRB240419A: Skynet Optical Afterglow Analysis
  71. GRB240418A - Candidate afterglow from NIRES
  72. IceCube Alert 240419.98: Global MASTER-Net observations report
  73. GRB 240419B: Swift/UVOT Upper Limits
  74. EP240420a: EP-WXT detection of a fast X-ray transient
  75. GRB 240419A: Swift/UVOT Upper Limits
  76. GRB 240419B: Swift-XRT refined Analysis
  77. GRB 240419B: optical afterglow from the NOT
  78. LIGO/Virgo/KAGRA S240420aw: Retraction of GW compact binary merger candidate
  79. Swift GRB 240419B: Global MASTER-Net observations report
  80. Swift GRB 240419A: Global MASTER-Net observations report
  81. GRB 240418A: Swift/UVOT Upper Limits
  82. GRB 240419A: REM NIR afterglow detection
  83. GRB 240419A: Swift-XRT refined Analysis
  84. GRB 240418A: Swift-XRT refined Analysis
  85. GRB 240419B: Swift detection of a burst
  86. GRB 240411B: Swift/UVOT Detection
  87. Fermi trigger No 735089036: Global MASTER-Net observations report
  88. EP240414a: GMG observation
  89. GRB 240419A: Swift detection of a burst
  90. GRB 240418A: NOT optical upper limits
  91. GRB 240418A: AKO Upper Limit
  92. GRB 240411A: GOTO early optical upper limits
  93. Swift GRB240418.85: Global MASTER-Net observations report
  94. GRB 240418A: Swift detection of a burst
  95. EP240417a: EP-WXT detection of a fast X-ray transient
  96. Fermi GRB 240417A: Global MASTER-Net observations report
  97. LIGO/Virgo/KAGRA S240413p: X-ray upper limits from EP-WXT for the candidate AGN counterpart
  98. GRB 240417A: Fermi GBM Final Real-time Localization
  99. GRB 240415B: GECAM-B detection
  100. EP 240416a: Xinglong and NOT decaying optical counterpart

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