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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"

39254 results found.

  1. Fermi trigger No 737152719: Global MASTER-Net observations report
  2. GRB 240511A: Prompt enhanced Swift-XRT position
  3. GRB 240511A: Swift detection of a burst
  4. GRB 240511A: Fermi GBM Final Real-time Localization
  5. Fermi trigger No 737102480: Global MASTER-Net observations report
  6. Fermi trigger No 737111207: Global MASTER-Net observations report
  7. Fermi Gamma-ray Burst Monitor trigger 737076431/240510977 is not a GRB
  8. LIGO/Virgo/KAGRA S240422ed: Candidates from the latest GW-MMADS DECam Observations
  9. Fermi trigger No 736967879: Global MASTER-Net observations report
  10. Fermi Gamma-ray Burst Monitor trigger 230925241/717313591 is not a GRB
  11. EP240506a: CrAO ZTSH optical upper limit
  12. GRB 240504A: Fermi GBM Observation
  13. Fermi Gamma-ray Burst Monitor trigger 736837160/240508208 is not a GRB
  14. EP240506a: Archival radio searching
  15. EP240506a: TRT optical upper limit
  16. Fermi trigger No 736733320: Global MASTER-Net observations report
  17. IPN triangulation of GRB 240504A
  18. GRB 240502A: 1.3m DFOT Optical upper limit
  19. GRB 240504A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  20. Fermi trigger No 736564880: Global MASTER-Net observations report
  21. GRB 240502C: Zeiss-1000 at Koshka observatory observations of GOTO optical counterpart candidates
  22. Fermi trigger No 736461232: Global MASTER-Net observations report
  23. IPN triangulation of GRB 240501B and GRB 240501A - possible episodes of ultra long GRB
  24. Fermi GRB 240504A: Global MASTER-Net observations report
  25. Fermi trigger No 736472503: Global MASTER-Net observations report
  26. GRB 240503A: AstroSat CZTI detection
  27. GRB 240504A: BALROG localization (Fermi Trigger 736492377 / GRB 240504217)
  28. GRB 240504A: Fermi GBM Final Real-time Localization
  29. Fermi trigger No 736387941: Global MASTER-Net observations report
  30. LXT 240402A / GRB 240402B: VLT X-shooter redshift of host
  31. GRB 240502A: GOTO optical upper limit
  32. Fermi trigger No 736379109: Global MASTER-Net observations report
  33. GRB 240502A: Fermi GBM Observation
  34. GRB 240415A 1.3m DFOT Optical upper limit
  35. GRB 240502C: GOTO possible optical counterpart candidates
  36. Fermi GRB 240502B: Global MASTER-Net observations report
  37. GRB 240502C: Fermi GBM Final Localization
  38. Fermi GRB 240502A: Global MASTER-Net observations report
  39. GRB 240501B: GRBAlpha detection
  40. GRB 240430A: GRBAlpha detection
  41. GRB 240502B: Fermi GBM Final Real-time Localization
  42. Integral GRB240502.23: Global MASTER-Net observations report
  43. GRB 240502A long GRB detected by INTEGRAL
  44. GRB 240502A: Fermi GBM Final Real-time Localization
  45. LIGO/Virgo/KAGRA S240422ed: Host redshifts of AT2024hfq, AT2024hfu, and AT2024hmo from DBSP
  46. Fermi GRB 240501A: Global MASTER-Net observations report
  47. Fermi trigger No 736197684: Global MASTER-Net observations report
  48. GRB 240426A: VZLUSAT-2 detection
  49. GRB 240425A: VZLUSAT-2 detection
  50. MeerKAT Discovery of a Probable Radio Counterpart to EP240414a
  51. GRB240430A: Fermi GBM Final Localization
  52. GRB 240501B: AstroSat CZTI detection
  53. GRB 240501A: Fermi GBM Final Real-time Localization
  54. GRB 240408B: VZLUSAT-2 detection
  55. GRB 240407A: VZLUSAT-2 detection
  56. X-ray transient EP240414a: Detection of associated supernova
  57. LIGO/Virgo/KAGRA S240422ed: GECKO/7DT ToO observations
  58. GRB 240425A: GRBAlpha detection
  59. Fermi-LAT gamma-ray observations of IceCube-240424A
  60. GRB 240429A: Fermi GBM Final Real-time Localization
  61. Fermi GRB 240428A: Global MASTER-Net observations report
  62. GRB 240428A: Fermi GBM Final Real-time Localization
  63. GRB 240426A: AstroSat CZTI detection
  64. LIGO/Virgo/KAGRA S240422ed: BOOTES-4/MET Optical Upper Limits for EP240426a
  65. GRB 240414A: NOEMA detection
  66. LIGO/Virgo/KAGRA S240422ed: EP-FXT detection of a candidate counterpart EP240426a
  67. S240422ed: BlackGEM/MeerLICHT transient detection AT2024hgl/MLTJ080628.10-250116.4
  68. LIGO/Virgo/KAGRA S240422ed: PRIME near-infrared observations
  69. S240422ed: MeerLICHT/BlackGEM photometry on AT2024hfx and archival ZTF detection
  70. LIGO/Virgo/KAGRA S240422ed: Upper limits from GECAM Observations
  71. LIGO/Virgo/KAGRA S240422ed: No significant candidates in GRANDMA and Kilonova-Catcher galaxy targeting observations
  72. GRB 240425A: Fermi GBM Final Real-time Localization
  73. Fermi trigger No 735697285: Global MASTER-Net observations report
  74. GRB 240419B: Swift-BAT refined analysis
  75. GRB 240421B: Swift-BAT refined analysis
  76. GRB 240422A: Glowbug gamma-ray detection
  77. LIGO/Virgo/KAGRA S240422ed: Archival BlackGEM/MeerLICHT detections of AT 2024hdr & AT 2024hdq
  78. LIGO/Virgo/KAGRA S240422ed: No significant counterpart candidates in HAWC observations
  79. LIGO/Virgo/KAGRA S240422ed: Vetting of DECam Candidates Using Real-Time Resources and SAGUARO Infrastructure
  80. IceCube-240424A - IceCube observation of a high-energy neutrino candidate track-like event
  81. GRB 240421B: GRBAlpha detection
  82. IceCube Alert 240424.08: Global MASTER-Net observations report
  83. LIGO/Virgo/KAGRA S240422ed: no candidate counterparts from Pan-STARRS observations of the skymap
  84. GRB 240419A: Swift-BAT refined analysis
  85. GRB 240418A: Swift-BAT refined analysis
  86. LXT240402A/GRB240402B: Chandra X-ray detection
  87. GRB 240419A: Possible ATCA radio detection
  88. GRB 240421B: ATCA radio observations
  89. LIGO/Virgo S240422ed: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  90. LIGO/Virgo/KAGRA S240422ed: Updated NED Galaxies in the Localization Volume
  91. LIGO/Virgo/KAGRA S240422ed: AstroSat CZTI non-detection and upper limits
  92. LIGO/Virgo/KAGRA S240422ed: Upper limits from Fermi-GBM Observations
  93. LIGO/Virgo/KAGRA S240421ar: Upper limits from Swift/BAT-GUANO
  94. LIGO/Virgo/KAGRA S240422ed: MeerLICHT and BlackGEM observations report
  95. LIGO/Virgo/Kagra S240422ed: NED Galaxies in the Localization Volume
  96. LIGO/Virgo/KAGRA S240422ed: Global MASTER-Net observations report
  97. Fermi trigger No 735470374: Global MASTER-Net observations report
  98. GRB 240421A: Glowbug gamma-ray detection
  99. GRB 240414A: radio detection with the VLA
  100. Fermi-LAT gamma-ray observations of IceCube-240419A

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