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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"

42476 results found.

  1. Fermi GRB 251113A: Global MASTER-Net observations report
  2. GRB 251113A: BALROG localization (Fermi Trigger 784748255 / GRB 251113734)
  3. GRB 251113A: Fermi GBM Final Real-time Localization
  4. GRB 251111A: SVOM/ECLAIRs refined analysis
  5. GRB 251025B: SVOM/ECLAIRs refined analysis
  6. GRB 251112A: Swift/UVOT Upper Limits
  7. LIGO/Virgo/KAGRA S251112cm: ATLAS pre-detections of AT2025adgp and AT2025adgq
  8. GRB 251112A: Swift-XRT refined Analysis
  9. GRB 251108C: AstroSat CZTI detection
  10. LIGO/Virgo/KAGRA S251112cm: Detection of two young transients by BlackGEM/MeerLICHT: AT2025adgp and AT2025adgq
  11. GRB 251112B: MAXI/GSC detection
  12. LIGO/Virgo/KAGRA S251112cm: Coverage and upper limits from MAXI/GSC observations
  13. LIGO/Virgo/KAGRA S251112cm: Initial GOTO-South observations
  14. GRB 251108B: Glowbug gamma-ray detection
  15. Swift Trigger 1413695: a possible GRB 251112A
  16. LIGO/Virgo/KAGRA S251112cm: Upper limits from Fermi-GBM Observations
  17. Fermi trigger No 784621743: Global MASTER-Net observations report
  18. LIGO/Virgo/KAGRA S251112cm: NED Galaxies in the 3-Initial Localization Volume
  19. GRB251111A: 1.3m DFOT optical upper limit
  20. LIGO/Virgo/KAGRA S251112cm: Identification of a GW compact binary merger candidate
  21. GRB 251106B: Glowbug gamma-ray detection of a likely short burst
  22. GRB 251111A: Swift-XRT afterglow detection
  23. GRB 251111A: SVOM/VT optical observations with X-band data
  24. SVOM GRB251111.42: Global MASTER-Net observations report
  25. GRB 251111A: Swift-XRT observations
  26. SVOM GRB251111.22: Global MASTER-Net observations report
  27. GRB 251111A: EP-FXT counterpart detection
  28. GRB 251013C: Chandra X-ray observations and jet break detection
  29. GRB 251111A: SVOM/VT optical observations with VHF data
  30. GRB 251111A: KAIT optical upper limit
  31. GRB 251111A: LCO optical observation
  32. GRB 251111A: SVOM/COLIBRÍ (FM-GFT) optical counterpart detection
  33. GRB 251111A: SVOM detection of a soft burst
  34. GRB 251103B: Swift-BAT refined analysis
  35. GRB 251106A: Swift/UVOT Upper Limits
  36. GRB 251105B: Insight-HXMT/HE detection
  37. GRB 251106B: Insight-HXMT detection
  38. LIGO/Virgo/KAGRA S251108fi: DDOTI Optical Candidate
  39. GRB 251105A: AstroSat CZTI detection
  40. LIGO/Virgo/KAGRA S251108fi: One counterpart neutrino candidate from IceCube neutrino searches
  41. IceCube-Cascade 251107A: Upper limits from a search for additional neutrino events in IceCube
  42. GRB 251108A: Fermi GBM Final Localization Correction
  43. Fermi trigger No 784329591: Global MASTER-Net observations report
  44. LIGO/Virgo/KAGRA S251108fi: Identification of a GW compact binary merger candidate
  45. Fermi trigger No 784279167: Global MASTER-Net observations report
  46. SVOM GRB251108.54: Global MASTER-Net observations report
  47. GRB 251102B: SVOM/GRM observation
  48. LIGO/Virgo/KAGRA S251108dn: Identification of a GW compact binary merger candidate
  49. The EP-WXT trigger 01709248051 is likely a flaring star
  50. SVOM GRB251106.83: Global MASTER-Net observations report
  51. IPN triangulation of GRB 251105B (possible sGRB with EE)
  52. GRB 251106A: SVOM/COLIBRÍ (FM-GFT) fading of the optical counterpart
  53. GRB 251106B: SVOM/GRM observation of a short burst
  54. GRB 251106A: Swift-XRT afterglow detection
  55. GRB 251106A: Kilonova-Catcher optical upper limit
  56. Fermi GBM Sub-Threshold Detection of GRB 251106A
  57. GRB 251106A: Swift/BAT arcminute localization of a burst
  58. GRB 251106A: SVOM/COLIBRÍ (FM-GFT) detection of a likely optical counterpart
  59. GRB 251106A: MASTER optical observations
  60. GRB 251106A: SVOM detection of a burst
  61. GRB 251103B: AstroSat CZTI detection
  62. GRB 251025C: TERI Gamma-ray detection
  63. GRB 251016B: TERI Gamma-ray detection
  64. GRB 251016A: TERI Gamma-ray detection of a short burst
  65. GRB 250920C: TERI Gamma-ray detection
  66. Fermi trigger No 784034269: Global MASTER-Net observations report
  67. EP251102a: Xinglong 2.16-m clear-band observations of the optical counterpart
  68. GRB 251105A: Fermi GBM Observation
  69. GRB 251105C: Fermi GBM Final Localization Correction
  70. LIGO/Virgo/KAGRA S251031dw: Candidates from the Zwicky Transient Facility
  71. GRB 251105A: Swift/BAT-GUANO localization skymap of a burst
  72. GRB 251104A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  73. GRB 251105B: AstroSat CZTI detection of a short burst with extended emission
  74. GRB 251023A: SVOM/ECLAIRs detection of a burst through targeted search
  75. Fermi GBM Sub-Threshold Detection of GRB 251105B
  76. GRB 251103B: Swift/UVOT Upper Limits
  77. LIGO/Virgo/KAGRA S251105aj: Identification of a GW compact binary merger candidate
  78. GRB 251105B: SVOM/GRM observation of a possible short burst with extended emission
  79. Fermi GRB 251105A: Global MASTER-Net observations report
  80. GRB 251105A: Fermi GBM Final Real-time Localization
  81. GRB 251103B: Fermi GBM observation
  82. GRB 251104A: SVOM detection of a burst
  83. GRB 251028A: Insight-HXMT/HE detection
  84. GRB 251103A: Optical afterglow detection by ZTF’s public survey
  85. EP251102a: FTW optical and NIR observations
  86. GRB 251103A: WFST optical observations
  87. EP251102a: update of EP-FXT follow-up observation
  88. EP251102a: OHP/T193 optical observations
  89. GRB 251103A: OHP/T193 optical observations
  90. GRB 251103A: Xinglong 2.16m optical detection
  91. GRB 251103A: Insight-HXMT detection
  92. GRB 251103A: KAIT optical observations
  93. GRB 251103B: Nanshan/HMT optical upper limit
  94. GRB 251013C: 7DT detection and Medium-band SED of Afterglow
  95. GRB 251103A: Swift/BAT-GUANO arcminute localization of a burst
  96. GRB 251103B: MITSuME Akeno optical upper limits
  97. GRB 251103B: Swift-XRT refined Analysis
  98. Fermi GRB 251103A: Global MASTER-Net observations report
  99. LIGO/Virgo/KAGRA S251103f: Identification of a GW compact binary merger candidate
  100. EP251102a: NIR observations with WINTER

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