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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"

39259 results found.

  1. Fermi trigger No 737173236: Global MASTER-Net observations report
  2. Fermi GRB 240511A: Global MASTER-Net observations report
  3. Swift GRB 240511A: Global MASTER-Net observations report
  4. Fermi trigger No 737105243: Global MASTER-Net observations report
  5. Fermi Gamma-ray Burst Monitor trigger 737133200/240511634 is not a GRB
  6. Fermi trigger No 737152719: Global MASTER-Net observations report
  7. GRB 240511A: Prompt enhanced Swift-XRT position
  8. GRB 240511A: Swift detection of a burst
  9. GRB 240511A: Fermi GBM Final Real-time Localization
  10. Fermi trigger No 737102480: Global MASTER-Net observations report
  11. Fermi trigger No 737111207: Global MASTER-Net observations report
  12. Fermi Gamma-ray Burst Monitor trigger 737076431/240510977 is not a GRB
  13. LIGO/Virgo/KAGRA S240422ed: Candidates from the latest GW-MMADS DECam Observations
  14. Fermi trigger No 736967879: Global MASTER-Net observations report
  15. Fermi Gamma-ray Burst Monitor trigger 230925241/717313591 is not a GRB
  16. EP240506a: CrAO ZTSH optical upper limit
  17. GRB 240504A: Fermi GBM Observation
  18. Fermi Gamma-ray Burst Monitor trigger 736837160/240508208 is not a GRB
  19. EP240506a: Archival radio searching
  20. EP240506a: TRT optical upper limit
  21. Fermi trigger No 736733320: Global MASTER-Net observations report
  22. IPN triangulation of GRB 240504A
  23. GRB 240502A: 1.3m DFOT Optical upper limit
  24. GRB 240504A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  25. Fermi trigger No 736564880: Global MASTER-Net observations report
  26. GRB 240502C: Zeiss-1000 at Koshka observatory observations of GOTO optical counterpart candidates
  27. Fermi trigger No 736461232: Global MASTER-Net observations report
  28. IPN triangulation of GRB 240501B and GRB 240501A - possible episodes of ultra long GRB
  29. Fermi GRB 240504A: Global MASTER-Net observations report
  30. Fermi trigger No 736472503: Global MASTER-Net observations report
  31. GRB 240503A: AstroSat CZTI detection
  32. GRB 240504A: BALROG localization (Fermi Trigger 736492377 / GRB 240504217)
  33. GRB 240504A: Fermi GBM Final Real-time Localization
  34. Fermi trigger No 736387941: Global MASTER-Net observations report
  35. LXT 240402A / GRB 240402B: VLT X-shooter redshift of host
  36. GRB 240502A: GOTO optical upper limit
  37. Fermi trigger No 736379109: Global MASTER-Net observations report
  38. GRB 240502A: Fermi GBM Observation
  39. GRB 240415A 1.3m DFOT Optical upper limit
  40. GRB 240502C: GOTO possible optical counterpart candidates
  41. Fermi GRB 240502B: Global MASTER-Net observations report
  42. GRB 240502C: Fermi GBM Final Localization
  43. Fermi GRB 240502A: Global MASTER-Net observations report
  44. GRB 240501B: GRBAlpha detection
  45. GRB 240430A: GRBAlpha detection
  46. GRB 240502B: Fermi GBM Final Real-time Localization
  47. Integral GRB240502.23: Global MASTER-Net observations report
  48. GRB 240502A long GRB detected by INTEGRAL
  49. GRB 240502A: Fermi GBM Final Real-time Localization
  50. LIGO/Virgo/KAGRA S240422ed: Host redshifts of AT2024hfq, AT2024hfu, and AT2024hmo from DBSP
  51. Fermi GRB 240501A: Global MASTER-Net observations report
  52. Fermi trigger No 736197684: Global MASTER-Net observations report
  53. GRB 240426A: VZLUSAT-2 detection
  54. GRB 240425A: VZLUSAT-2 detection
  55. MeerKAT Discovery of a Probable Radio Counterpart to EP240414a
  56. GRB240430A: Fermi GBM Final Localization
  57. GRB 240501B: AstroSat CZTI detection
  58. GRB 240501A: Fermi GBM Final Real-time Localization
  59. GRB 240408B: VZLUSAT-2 detection
  60. GRB 240407A: VZLUSAT-2 detection
  61. X-ray transient EP240414a: Detection of associated supernova
  62. LIGO/Virgo/KAGRA S240422ed: GECKO/7DT ToO observations
  63. GRB 240425A: GRBAlpha detection
  64. Fermi-LAT gamma-ray observations of IceCube-240424A
  65. GRB 240429A: Fermi GBM Final Real-time Localization
  66. Fermi GRB 240428A: Global MASTER-Net observations report
  67. GRB 240428A: Fermi GBM Final Real-time Localization
  68. GRB 240426A: AstroSat CZTI detection
  69. LIGO/Virgo/KAGRA S240422ed: BOOTES-4/MET Optical Upper Limits for EP240426a
  70. GRB 240414A: NOEMA detection
  71. LIGO/Virgo/KAGRA S240422ed: EP-FXT detection of a candidate counterpart EP240426a
  72. S240422ed: BlackGEM/MeerLICHT transient detection AT2024hgl/MLTJ080628.10-250116.4
  73. LIGO/Virgo/KAGRA S240422ed: PRIME near-infrared observations
  74. S240422ed: MeerLICHT/BlackGEM photometry on AT2024hfx and archival ZTF detection
  75. LIGO/Virgo/KAGRA S240422ed: Upper limits from GECAM Observations
  76. LIGO/Virgo/KAGRA S240422ed: No significant candidates in GRANDMA and Kilonova-Catcher galaxy targeting observations
  77. GRB 240425A: Fermi GBM Final Real-time Localization
  78. Fermi trigger No 735697285: Global MASTER-Net observations report
  79. GRB 240419B: Swift-BAT refined analysis
  80. GRB 240421B: Swift-BAT refined analysis
  81. GRB 240422A: Glowbug gamma-ray detection
  82. LIGO/Virgo/KAGRA S240422ed: Archival BlackGEM/MeerLICHT detections of AT 2024hdr & AT 2024hdq
  83. LIGO/Virgo/KAGRA S240422ed: No significant counterpart candidates in HAWC observations
  84. LIGO/Virgo/KAGRA S240422ed: Vetting of DECam Candidates Using Real-Time Resources and SAGUARO Infrastructure
  85. IceCube-240424A - IceCube observation of a high-energy neutrino candidate track-like event
  86. GRB 240421B: GRBAlpha detection
  87. IceCube Alert 240424.08: Global MASTER-Net observations report
  88. LIGO/Virgo/KAGRA S240422ed: no candidate counterparts from Pan-STARRS observations of the skymap
  89. GRB 240419A: Swift-BAT refined analysis
  90. GRB 240418A: Swift-BAT refined analysis
  91. LXT240402A/GRB240402B: Chandra X-ray detection
  92. GRB 240419A: Possible ATCA radio detection
  93. GRB 240421B: ATCA radio observations
  94. LIGO/Virgo S240422ed: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  95. LIGO/Virgo/KAGRA S240422ed: Updated NED Galaxies in the Localization Volume
  96. LIGO/Virgo/KAGRA S240422ed: AstroSat CZTI non-detection and upper limits
  97. LIGO/Virgo/KAGRA S240422ed: Upper limits from Fermi-GBM Observations
  98. LIGO/Virgo/KAGRA S240421ar: Upper limits from Swift/BAT-GUANO
  99. LIGO/Virgo/KAGRA S240422ed: MeerLICHT and BlackGEM observations report
  100. LIGO/Virgo/Kagra S240422ed: NED Galaxies in the Localization Volume

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