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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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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

15271 results found.

  1. GRB 251130B: AstroSat CZTI detection
  2. EP251130a: SAO RAS optical observations
  3. EP251130a: refined analysis of the EP-WXT and EP-FXT observations
  4. EP251130a: JinShan optical observations
  5. GRB 251127A: SVOM/GRM observation
  6. IceCube-251130A - IceCube observation of a high-energy neutrino candidate track-like event
  7. EP251130a: Swift-XRT counterpart detection
  8. EP251129a/GRB 251129A: EP-FXT follow-up observations
  9. GRB 251129A / EP251129a: GTC/OSIRIS+ spectroscopic redshift z = 1.460
  10. GRB 251129A / EP251129a: OSN and CAHA optical follow-up
  11. GRB 251128A: AstroSat CZTI detection
  12. GRB 251128A: GECAM-B detection
  13. GRB 251128A: SVOM/GRM observation of a long burst
  14. GRB 251128A: Insight-HXMT/HE detection
  15. GRB 251129A: Swift ToO observations
  16. GRB 251129A: SVOM/VT optical counterpart confirmation with VHF data
  17. GRB 251129A: SVOM detection of a burst
  18. GRB 251129A: SVOM detection of a burst
  19. GRB 251128A: Swift/BAT-GUANO localization skymap of a burst
  20. GRB 251126A: OHP/T193 optical observations and tentative spectroscopic redshift
  21. GRB 250702B: detection of the compact radio counterpart 139 days after the burst
  22. GRB 251126A NUTTelA-TAO Early Measurements
  23. EP251124a: Pan-STARRS ri-band imaging and photometry
  24. GRB 251126A : MITSuME Akeno optical afterglow candidate detection
  25. GRB 251126A: NOT optical observations
  26. GRB 251126A: COLIBRÍ photometric redshift z = 3.5
  27. GRB 251125B: GECAM-B detection
  28. GRB 251126A: Kilonova-Catcher optical afterglow detection
  29. GRB 251126A: Nanshan/HMT optical afterglow detection
  30. GRB 251126A: Swift detection of a burst
  31. EP251124a: NOT r- and z-band optical upper limits
  32. GRB 251124A: Fermi GBM Localization by automated pipeline
  33. LIGO/Virgo/KAGRA S251112cm: AT 2025adht Kinder follow-up observations
  34. EP251124a: Optical upper limit with Kinder observations
  35. LIGO/Virgo/KAGRA S251105aj: SVOM/VT optical observations and preliminary results on SVOM J2320.0-2901
  36. LIGO/Virgo/KAGRA S251105aj: EP-FXT follow-up observations and preliminary results on SVOM J2320.0-2901
  37. EP251124a: Einstein Probe detection of an X-ray transient
  38. GRB 251116C: Swift-XRT confirmation of fading
  39. GRB 251122A / EP251122a: EP-FXT counterpart detection
  40. GRB 251122A / EP251122a: WFST optical observations
  41. GRB 251122A/EP251122a: SVOM/VT optical observations with VHF data
  42. GRB 251122A/EP251122a: Additional, deeper LCO optical r band upper limit
  43. GRB 251122A / EP251122a: LCO optical upper limits
  44. GRB 251122A / EP251122a: SVOM detection of a long burst
  45. LIGO/Virgo/KAGRA S251105aj: SVOM/ECLAIRs detection of a high-energy transient SVOM J2320.0-2901 through targeted search
  46. LIGO/Virgo/KAGRA S251112cm: SOAR spectroscopy of three TROVE TNS candidates
  47. GRB 251121A: Swift/BAT-GUANO localization skymap of a short burst
  48. GRB 251103A: SVOM/ECLAIRs and SVOM/GRM joint refined analysis
  49. GRB 251118A: GECAM-B detection
  50. LIGO/Virgo/KAGRA S251112cm: SVOM/VT optical observations and preliminary results
  51. EP251118a / GRB 251118C: SVOM/VT optical observation
  52. The EP-WXT trigger 01709248403 is likely a flaring star
  53. GRB 251118C: Glowbug gamma-ray detection of the fast X-ray transient EP251118A
  54. GRB 251118C: Swift/BAT rates detection of a burst with a possible association with EP 251118A
  55. GRB 251118C: SVOM/GRM observation of a possible gamma-ray counterpart of EP251118a
  56. Konus-Wind detection of GRB 251118C (EP251118a)
  57. GRB 251117A: Insight-HXMT/HE detection
  58. GRB 251116D: SVOM/GRM observation of a long GRB
  59. GRB 251119A: SVOM detection of a possible burst
  60. EP251118a: preliminary result of EP-FXT follow-up observation
  61. GRB 251118A: Fermi-LAT detection
  62. GRB 251118A: Swift ToO observations
  63. LIGO/Virgo/KAGRA S251112cm: Upper limits from Glowbug gamma-ray observations
  64. GRB 251116C: SVOM/ECLAIRs refined analysis
  65. GRB 251116B: SVOM/ECLAIRs refined analysis
  66. GRB 251117A: AstroSat CZTI detection
  67. GRB 251114B: Insight-HXMT/HE detection
  68. GRB 251114B: GECAM-B detection of a short burst
  69. GRB 251117A: Fermi GBM observation
  70. GRB 251116D: Insight-HXMT/HE detection
  71. GRB 251117A: Swift/BAT-GUANO localization skymap of a short burst
  72. GRB 251117A: SVOM/GRM observation of a short burst
  73. GRB 251117A: Tiled Swift observations
  74. GRB 251117A: Fermi-LAT detection
  75. LIGO/Virgo/KAGRA S251112cm: Classification of reported candidates with SOAR/Goodman
  76. GRB 251116B: SVOM/VT optical upper limit
  77. LIGO/Virgo/KAGRA S251112cm: WFST follow-up observations and preliminary results
  78. GRB 251116D: AstroSat CZTI detection
  79. LIGO/Virgo/KAGRA S251112cm: Observations with the NSF-DOE Vera C. Rubin Observatory
  80. GRB 251116C: SVOM detection of a burst
  81. GRB 251116B: SVOM detection of a burst
  82. IceCube-Cascade 251112A: Upper limits from a search for additional neutrino events in IceCube
  83. LIGO/Virgo/KAGRA S251112cm: GRANDMA observations of the skymap
  84. LIGO/Virgo/KAGRA S251112cm: AT2025adht follow-up at Maidanak observatory by GRANDMA
  85. GRB 251115A: Tiled Swift observations
  86. GRB 251115A: Fermi-LAT detection
  87. GRB 251013C: joint SVOM/ECLAIRs-GRM refined analysis
  88. LIGO/Virgo/KAGRA S251112cm: DECam GW-MMADS candidates
  89. GRB 251113A: AstroSat CZTI detection
  90. Konus-Wind detection of GRB 251108C
  91. Konus-Wind detection of GRB 251103A
  92. LIGO/Virgo/KAGRA S251112cm: ATLAS targeted observations of the skymap
  93. LIGO/Virgo/KAGRA S251112cm: Candidates from the Zwicky Transient Facility
  94. LIGO/Virgo/KAGRA S251112cm: TROVE Vetting of TNS Candidates
  95. GRB 251111A: SVOM/ECLAIRs refined analysis
  96. GRB 251025B: SVOM/ECLAIRs refined analysis
  97. GRB 251108C: AstroSat CZTI detection
  98. LIGO/Virgo/KAGRA S251112cm: Coverage and upper limits from MAXI/GSC observations
  99. LIGO/Virgo/KAGRA S251112cm: Upper limits from Fermi-GBM Observations
  100. GRB 251111A: Swift-XRT observations

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