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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"

22204 results found.

  1. LIGO/Virgo/KAGRA S240422ed: DECam GW-MMADS Candidates
  2. LIGO/Virgo/KAGRA S240422ed: Potential Magellan candidates from GCN 36263 are unrelated.
  3. LIGO/Virgo/KAGRA S240422ed: NOT J-band upper limit on the Swift/XRT source S240422ed_X61
  4. LIGO/Virgo/KAGRA S240422ed: X-ray Upper Limits from EP-WXT for the Three Potential Electromagnetic Counterparts Reported So Far
  5. IceCube Alert 240424.08: Global MASTER-Net observations report
  6. LIGO/Virgo/KAGRA S240422ed: Magellan Detection of a Potential Electromagnetic Counterpart
  7. LIGO/Virgo/KAGRA S240422ed: SAGUARO upper limits from CSS
  8. LIGO/Virgo/KAGRA S240422ed: Subaru/MOIRCS near-infrared observations by J-GEM Collaboration
  9. LIGO/Virgo/KAGRA S240422ed: LAST optical observations
  10. LIGO/Virgo/KAGRA S240422ed: Potential Candidates from Magellan galaxy-based search
  11. LIGO/Virgo/KAGRA S240422ed: WINTER J-band upper limits on the Swift/XRT source S240422ed_X61
  12. LIGO/Virgo/KAGRA S240422ed: no candidate counterparts from Pan-STARRS observations of the skymap
  13. LIGO/Virgo/KAGRA S240422ed: GOTO counterpart search
  14. LIGO/Virgo/KAGRA S240422ed: No Counterparts in DDOTI/OAN Optical Observations
  15. LXT240402A/GRB240402B: Chandra X-ray detection
  16. LIGO/Virgo/KAGRA S240422ed: no candidate counterparts from ATLAS observations
  17. GRB 240419A: Possible ATCA radio detection
  18. GRB 240421B: ATCA radio observations
  19. LIGO/Virgo/KAGRA S240422ed: WINTER near-infrared J-band observations
  20. LIGO/Virgo S240422ed: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  21. LIGO/Virgo/KAGRA S240422ed: Zwicky Transient Facility observations and candidates
  22. LIGO/Virgo/KAGRA S240422ed: GW-MMADS DECam observations
  23. LIGO/Virgo/KAGRA S240422ed: Magellan Observations
  24. LIGO/Virgo/KAGRA S240422ed: Updated NED Galaxies in the Localization Volume
  25. LIGO/Virgo/KAGRA S240422ed: Upper limits from Fermi-GBM Observations
  26. LIGO/Virgo/KAGRA S240421ar: Upper limits from Swift/BAT-GUANO
  27. LIGO/Virgo/KAGRA S240422ed: Coverage and upper limits from MAXI/GSC observations
  28. LIGO/Virgo/KAGRA S240422ed: MeerLICHT and BlackGEM observations report
  29. LIGO/Virgo/Kagra S240422ed: NED Galaxies in the Localization Volume
  30. LIGO/Virgo/KAGRA S240422ed: Global MASTER-Net observations report
  31. Fermi trigger No 735470374: Global MASTER-Net observations report
  32. GRB 240414A: radio detection with the VLA
  33. Fermi-LAT gamma-ray observations of IceCube-240419A
  34. GRB 240414A: AMI-LA radio observations
  35. GRB 240414A: LBT optical detection
  36. GRB 240415B: Swift-XRT observations
  37. Fermi GRB 240422A: Global MASTER-Net observations report
  38. GRB240421B: Zadko Observations
  39. Fermi GRB 240421B: Global MASTER-Net observations report
  40. Swift GRB 240421B: Global MASTER-Net observations report
  41. GRB 240421B: J-band upper limits from WINTER
  42. GRB 240421B: Swift/UVOT Upper Limits
  43. Fermi GRB 240421A: Global MASTER-Net observations report
  44. EP240420a: TNT upper limit to its optical counterpart
  45. EP240420a: Xinglong decaying optical counterpart
  46. EP240420a: Nanshan optical counterpart observations
  47. EP240420a: NOT optical counterpart candidate and potential host
  48. Fermi trigger No 735280430: Global MASTER-Net observations report
  49. GRB240418A - Candidate afterglow from NIRES
  50. IceCube Alert 240419.98: Global MASTER-Net observations report
  51. GRB 240419B: Swift/UVOT Upper Limits
  52. GRB 240419A: Swift/UVOT Upper Limits
  53. GRB 240419B: optical afterglow from the NOT
  54. EP240414a: Near-IR observations with NIRES and WINTER
  55. Swift GRB 240419B: Global MASTER-Net observations report
  56. Swift GRB 240419A: Global MASTER-Net observations report
  57. GRB 240418A: Swift/UVOT Upper Limits
  58. GRB 240419A: REM NIR afterglow detection
  59. GRB 240411B: Swift/UVOT Detection
  60. GRB 240419A: VLT/UVES redshift of z = 5.178
  61. GRB 240419A: VLT optical afterglow detection
  62. Fermi trigger No 735089036: Global MASTER-Net observations report
  63. EP240416a: J-band observations with WINTER
  64. GRB 240418A: TSHAO Zeiss-1000 optical upper limit
  65. GRB 240418A: NOT optical upper limits
  66. GRB 240411A: GOTO early optical upper limits
  67. Swift GRB240418.85: Global MASTER-Net observations report
  68. EP240417a: EP-WXT detection of a fast X-ray transient
  69. Fermi GRB 240417A: Global MASTER-Net observations report
  70. LIGO/Virgo/KAGRA S240413p: X-ray upper limits from EP-WXT for the candidate AGN counterpart
  71. EP240414a: GSP detects optical candidate counterpart AT2024gsa
  72. LIGO/Virgo/KAGRA S240413p: DECam GW-MMADS candidates
  73. EP240414a: Pan-STARRS detects re-brightening of the candidate counterpart AT2024gsa
  74. LIGO/Virgo/KAGRA S240413p: historical ATLAS and ZTF observations of the candidate AGN counterpart
  75. LIGO/Virgo/KAGRA S240413p: STEP - T80S Search and Candidate Counterpart Identification
  76. EP240416A: MASTER optical observations
  77. EP240416a: Kinder optical counterpart candidate
  78. EP240416a: EP-WXT detection of a fast X-ray transient
  79. GRB 240414A: AbAO optical upprer limit
  80. GRB 240415A: Swift/UVOT Detection
  81. GRB 240414A: GAD Observatory, La Spezia, Italy ,upper limit
  82. GRB 240415A: Earliest optical followup with the Kinder observations
  83. GRB 240415B: Swift ToO observations
  84. GRB 240415B: Swift/BAT-GUANO Correction
  85. GRB 240415B: Swift/BAT-GUANO arcminute localization of a short burst
  86. GRB 240415A: OHP/T193 optical observations
  87. GRB 240415A: optical afterglow detection from the INAF Asiago Observatory
  88. GRB 240415A: SAO RAS optical observations
  89. Fermi GRB 240415A: Global MASTER-Net observations report
  90. GRB 240415A: Mondy optical transient detection
  91. GRB 240414A: Photometric observation from 2.2m CAHA
  92. GRB 240414A: Swift/UVOT Detection
  93. LXT 240402A/GRB 240402B: Swift follow-up observations
  94. GRB 240414A: Mondy optical observations
  95. X-ray transient EP 240414a - GTC spectroscopic observations
  96. GRB 240415A: Prompt Swift-XRT observations
  97. EP 240414a: NOT optical counterpart confirmation
  98. GRB240414A : J-band upper limits from WINTER
  99. GRB 240414A : OHP/T193 second epoch of optical follow-up and afterglow detection
  100. GRB 240414A: MarSEC Observatory, Vicenza, Italy, UPPER LIMIT

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