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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"

45798 results found.

  1. GRB240421B: Zadko Observations
  2. Fermi GRB 240421B: Global MASTER-Net observations report
  3. Swift GRB 240421B: Global MASTER-Net observations report
  4. GRB 240421B: Fermi GBM Observation
  5. GRB 240421B: Swift-XRT refined Analysis
  6. GRB240421B: BOOTES-5/JGT optical upper limit
  7. GRB 240421B: J-band upper limits from WINTER
  8. GRB 240421B: Swift/UVOT Upper Limits
  9. GRB 240421B: Enhanced Swift-XRT position
  10. Fermi GRB 240421A: Global MASTER-Net observations report
  11. EP240417a: no counterpart detection by SOAR
  12. EP240420a: TNT upper limit to its optical counterpart
  13. EP240420a: Xinglong decaying optical counterpart
  14. GRB 240421B: Swift detection of a burst
  15. EP240420a: Nanshan optical counterpart observations
  16. EP240420a: GWAC-F50A optical upper limit
  17. LIGO/Virgo/KAGRA S240421ar: Identification of a GW unmodeled transient candidate
  18. GRB 240421A: Fermi GBM Final Real-time Localization
  19. EP240420a: detection of fading X-ray emission with refined position by EP-FXT
  20. EP240420a: NOT optical counterpart candidate and potential host
  21. Fermi trigger No 735280430: Global MASTER-Net observations report
  22. GRB240419A: Skynet Optical Afterglow Analysis
  23. GRB240418A - Candidate afterglow from NIRES
  24. IceCube Alert 240419.98: Global MASTER-Net observations report
  25. GRB 240419B: Swift/UVOT Upper Limits
  26. IceCube-240419A - IceCube observation of a high-energy neutrino candidate track-like event
  27. IceCube-240419A - IceCube observation of a high-energy neutrino candidate track-like event
  28. EP240420a: EP-WXT detection of a fast X-ray transient
  29. GRB 240419A: Swift/UVOT Upper Limits
  30. GRB 240419B: Swift-XRT refined Analysis
  31. GRB 240419B: optical afterglow from the NOT
  32. LIGO/Virgo/KAGRA S240420aw: Retraction of GW compact binary merger candidate
  33. EP240414a: Near-IR observations with NIRES and WINTER
  34. Swift GRB 240419B: Global MASTER-Net observations report
  35. EP240414A: Terskol Zeiss-2000 optical upper limit
  36. GRB 240419B: Enhanced Swift-XRT position
  37. Swift GRB 240419A: Global MASTER-Net observations report
  38. GRB 240418A: Swift/UVOT Upper Limits
  39. GRB 240419A: REM NIR afterglow detection
  40. GRB 240419A: Swift-XRT refined Analysis
  41. GRB 240418A: Swift-XRT refined Analysis
  42. GRB 240419B: Swift detection of a burst
  43. GRB 240411B: Swift/UVOT Detection
  44. EP240417a: YAHPT Optical Upper Limits
  45. GRB240418A: YAHPT Upper Limits
  46. GRB 240419A: VLT/UVES redshift of z = 5.178
  47. GRB 240419A: VLT optical afterglow detection
  48. GRB 240419A: Enhanced Swift-XRT position
  49. Fermi trigger No 735089036: Global MASTER-Net observations report
  50. EP240416a: J-band observations with WINTER
  51. EP240414a: GMG observation
  52. GRB 240419A: Prompt enhanced Swift-XRT position
  53. GRB 240419A: Swift detection of a burst
  54. GRB 240418A: TSHAO Zeiss-1000 optical upper limit
  55. GRB 240418A: NOT optical upper limits
  56. GRB 240418A: Enhanced Swift-XRT position
  57. GRB 240418A: AKO Upper Limit
  58. GRB 240411A: GOTO early optical upper limits
  59. Swift GRB240418.85: Global MASTER-Net observations report
  60. GRB 240418A: Swift detection of a burst
  61. EP240417a: EP-WXT detection of a fast X-ray transient
  62. Fermi GRB 240417A: Global MASTER-Net observations report
  63. LIGO/Virgo/KAGRA S240413p: X-ray upper limits from EP-WXT for the candidate AGN counterpart
  64. EP240416A: Terskol Zeiss-2000 optical upper limit
  65. EP240416A: Khureltogoot optical upper limit
  66. Improved IPN triangulation of GRB 240411A
  67. EP240416a: BOOTES-2/TELMA Optical Upper Limit
  68. EP240414a: GSP detects optical candidate counterpart AT2024gsa
  69. LIGO/Virgo/KAGRA S240413p: DECam GW-MMADS candidates
  70. IceCube-Cascade 240416A: Upper limits from a search for additional neutrino events in IceCube
  71. GRB 240417A: Fermi GBM Final Real-time Localization
  72. EP240414a: Pan-STARRS detects re-brightening of the candidate counterpart AT2024gsa
  73. LIGO/Virgo/KAGRA S240413p: historical ATLAS and ZTF observations of the candidate AGN counterpart
  74. GRB 240415A: Glowbug gamma-ray detection
  75. GRB 240414A: Glowbug gamma-ray detection
  76. LIGO/Virgo/KAGRA S240413p: STEP - T80S Search and Candidate Counterpart Identification
  77. GRB 240415B: GECAM-B detection
  78. EP 240416a: Xinglong and NOT decaying optical counterpart
  79. GRB 240415A: Swift-BAT refined analysis
  80. EP240416A: MASTER optical observations
  81. GRB 240411A: Glowbug gamma-ray detection
  82. GRB 240414A: Swift-BAT refined analysis
  83. EP240416a: Kinder optical counterpart candidate
  84. EP240416a: EP-WXT detection of a fast X-ray transient
  85. GRB 240414A: AbAO optical upprer limit
  86. GRB 240415A: Swift/UVOT Detection
  87. EP240413a: BOOTES-2/TELMA Optical Upper Limit
  88. GRB 240415A: Fermi GBM Observation
  89. GRB 240414A: GAD Observatory, La Spezia, Italy ,upper limit
  90. GRB 240415A: Earliest optical followup with the Kinder observations
  91. GRB 240414A: GMG observation
  92. EP 240414a: BOOTES-4/MET Optical Upper Limits
  93. EP240414a: EP-FXT follow-up observation
  94. GRB 240415A: Enhanced Swift-XRT position
  95. GRB 240415B: Swift ToO observations
  96. GRB 240415B: Swift/BAT-GUANO arcminute localization of a short burst
  97. GRB 240415A: OHP/T193 optical observations
  98. GRB 240415A: optical afterglow detection from the INAF Asiago Observatory
  99. GRB 240415A: SAO RAS optical observations
  100. GRB 240415A: Mondy optical transient detection (photometry correction in GCN 36118 )

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