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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"

24519 results found.

  1. Fermi trigger No 737247400: Global MASTER-Net observations report
  2. Fermi trigger No 737244199: Global MASTER-Net observations report
  3. Fermi trigger No 737218721: Global MASTER-Net observations report
  4. Fermi trigger No 737196587: Global MASTER-Net observations report
  5. Fermi trigger No 737168073: Global MASTER-Net observations report
  6. GRB 240511A : MITSuME Akeno optical upper limits
  7. LIGO/Virgo/KAGRA S240512r: Updated Sky localization and EM Bright Classification
  8. GRB 240511A: Swift-XRT refined Analysis
  9. Fermi trigger No 737173236: Global MASTER-Net observations report
  10. LIGO/Virgo/KAGRA S240512r: Identification of a GW compact binary merger candidate
  11. Fermi GRB 240511A: Global MASTER-Net observations report
  12. Swift GRB 240511A: Global MASTER-Net observations report
  13. Fermi trigger No 737105243: Global MASTER-Net observations report
  14. Fermi trigger No 737152719: Global MASTER-Net observations report
  15. LIGO/Virgo/KAGRA S240511i: Updated Sky localization
  16. GRB 240511A: Fermi GBM Final Real-time Localization
  17. Fermi trigger No 737102480: Global MASTER-Net observations report
  18. Fermi trigger No 737111207: Global MASTER-Net observations report
  19. LIGO/Virgo/KAGRA S240511i: Identification of a GW compact binary merger candidate
  20. Fermi trigger No 736967879: Global MASTER-Net observations report
  21. EP240506a: Xinglong optical upper limit
  22. EP240506a: CrAO ZTSH optical upper limit
  23. GRB 240504A: Fermi GBM Observation
  24. LIGO/Virgo/KAGRA S240507p: Updated Sky localization and EM Bright Classification
  25. LIGO/Virgo/KAGRA S240422ed: Upper limits from a two-week IceCube neutrino search
  26. Fermi trigger No 736733320: Global MASTER-Net observations report
  27. IPN triangulation of GRB 240504A
  28. LIGO/Virgo/KAGRA S240507p: Identification of a GW compact binary merger candidate
  29. LIGO/Virgo/KAGRA S240422ed: Additional WINTER near-infrared J-band observations
  30. LIGO/Virgo/KAGRA S240422ed: Swope Follow-up of AT2024hfr and AT2024hfs
  31. GRB 240504A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  32. LIGO/Virgo/KAGRA S240505av: Updated Sky localization and EM Bright Classification
  33. Fermi trigger No 736564880: Global MASTER-Net observations report
  34. LIGO/Virgo/KAGRA S240505av: Identification of a GW compact binary merger candidate
  35. IceCube-240424A: GRANDMA Optical Upper Limit of Fermi J2151.3+0220
  36. GRB 240502C: Zeiss-1000 at Koshka observatory observations of GOTO optical counterpart candidates
  37. Fermi trigger No 736461232: Global MASTER-Net observations report
  38. IPN triangulation of GRB 240501B and GRB 240501A - possible episodes of ultra long GRB
  39. Fermi GRB 240504A: Global MASTER-Net observations report
  40. Fermi trigger No 736472503: Global MASTER-Net observations report
  41. GRB 240504A: BALROG localization (Fermi Trigger 736492377 / GRB 240504217)
  42. GRB 240504A: Fermi GBM Final Real-time Localization
  43. Fermi trigger No 736387941: Global MASTER-Net observations report
  44. LXT 240402A / GRB 240402B: VLT X-shooter redshift of host
  45. Fermi trigger No 736379109: Global MASTER-Net observations report
  46. GRB 240502A: Fermi GBM Observation
  47. GRB 240502C: GOTO possible optical counterpart candidates
  48. LIGO/Virgo/KAGRA S240501an: Updated Sky localization and EM Bright Classification
  49. LIGO/Virgo/KAGRA S240430ca: Updated Sky localization and EM Bright Classification
  50. Fermi GRB 240502B: Global MASTER-Net observations report
  51. GRB 240502C: Fermi GBM Final Localization
  52. Fermi GRB 240502A: Global MASTER-Net observations report
  53. GRB 240501B: GRBAlpha detection
  54. GRB 240430A: GRBAlpha detection
  55. GRB 240502B: Fermi GBM Final Real-time Localization
  56. Integral GRB240502.23: Global MASTER-Net observations report
  57. GRB 240502A: Fermi GBM Final Real-time Localization
  58. Fermi GRB 240501A: Global MASTER-Net observations report
  59. Fermi trigger No 736197684: Global MASTER-Net observations report
  60. GRB 240426A: VZLUSAT-2 detection
  61. GRB 240425A: VZLUSAT-2 detection
  62. MeerKAT Discovery of a Probable Radio Counterpart to EP240414a
  63. GRB240430A: Fermi GBM Final Localization
  64. GRB 240501A: Fermi GBM Final Real-time Localization
  65. GRB 240408B: VZLUSAT-2 detection
  66. GRB 240407A: VZLUSAT-2 detection
  67. LIGO/Virgo/KAGRA S240501an: Identification of a GW compact binary merger candidate
  68. X-ray transient EP240414a: Detection of associated supernova
  69. LIGO/Virgo/KAGRA S240430ca: Updated Sky localization and EM Bright Classification
  70. LIGO/Virgo/KAGRA S240430ca: Identification of a GW compact binary merger candidate
  71. LIGO/Virgo/KAGRA S240422ed: GECKO/7DT ToO observations
  72. GRB 240425A: GRBAlpha detection
  73. Fermi-LAT gamma-ray observations of IceCube-240424A
  74. LIGO/Virgo/KAGRA S240426s: Updated Sky localization
  75. LIGO/Virgo/KAGRA S240426dl: Updated Sky localization
  76. GRB 240429A: Fermi GBM Final Real-time Localization
  77. LIGO/Virgo/KAGRA S240428dr: Updated Sky localization
  78. LIGO/Virgo/KAGRA S240422ed: GECKO/KMTNet ToO observations
  79. LIGO/Virgo/KAGRA S240429an: Retraction of GW compact binary merger candidate
  80. LIGO/Virgo/KAGRA S240428dr: Identification of a GW compact binary merger candidate
  81. Fermi GRB 240428A: Global MASTER-Net observations report
  82. GRB 240428A: Fermi GBM Final Real-time Localization
  83. LIGO/Virgo/KAGRA S240422ed: Observations with 1.6m Mephisto
  84. GRB 240426A: AstroSat CZTI detection
  85. EP240426a: YAHPT optical upper limit
  86. XMM-Newton observation of EP240426a
  87. LIGO/Virgo/KAGRA S240426dl: Identification of a GW compact binary merger candidate
  88. LIGO/Virgo/KAGRA S240422ed: BOOTES-4/MET Optical Upper Limits for EP240426a
  89. LIGO/Virgo/KAGRA S240422ed: EP-FXT Detection of the Potential Opitcal Electromagnetic Counterpart AT 2024hfq Reported by DECam
  90. LIGO/Virgo/KAGRA S240422ed: EP240426a possible optical detection
  91. LIGO/Virgo/KAGRA S240422ed: Continued Magellan Observations
  92. LVK S240422ed: Further Swift-XRT followup of three sources
  93. LIGO/Virgo/KAGRA S240422ed: EP-FXT detection of a candidate counterpart EP240426a
  94. LIGO/Virgo/KAGRA S240426s: Identification of a GW compact binary merger candidate
  95. LIGO/Virgo/KAGRA S240422ed: Zwicky Transient Facility contuinued observations of S240422ed and candidate analysis
  96. IceCube-240424A: Upper limits from a search for additional neutrino events in IceCube
  97. LIGO/Virgo/KAGRA S240422ed: Further near-infrared observations with Subaru/MOIRCS by J-GEM Collaboration
  98. LIGO/Virgo/KAGRA S240422ed: X-ray Upper Limits from EP-FXT for the Potential Electromagnetic Counterparts Reported by Swift and DECam
  99. LIGO/Virgo/KAGRA S240422ed: Upper limits from GECAM Observations
  100. LIGO/Virgo/KAGRA S240422ed: No significant candidates in GRANDMA and Kilonova-Catcher galaxy targeting observations

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