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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.

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23700 results found.

  1. GRB 251118C: SVOM/GRM observation of a possible gamma-ray counterpart of EP251118a
  2. Konus-Wind detection of GRB 251118C (EP251118a)
  3. GRB 251119A: SVOM trigger sb25111901 is not a GRB
  4. EP251118a: GOTO optical afterglow detection
  5. GRB 251118A: Fermi-LAT detection
  6. LIGO/Virgo/KAGRA S251112cm: Upper limits from Glowbug gamma-ray observations
  7. GRB 251116C: SVOM/ECLAIRs refined analysis
  8. GRB 251116B: SVOM/ECLAIRs refined analysis
  9. GRB 251117A: AstroSat CZTI detection
  10. GRB 251013C: Koshka, SAO RAS, Mondy, and CrAO optical observations, possible SN detection
  11. GRB 251115A: Swift-XRT observations
  12. LIGO/Virgo/KAGRA S251117dq: Identification of a GW compact binary merger candidate
  13. LIGO/Virgo/KAGRA S251112cm: J-GEM follow-up observations
  14. LIGO/Virgo/KAGRA S251112cm: Classification of reported candidates with SOAR/Goodman
  15. GRB 251116B: SVOM/VT optical upper limit
  16. LIGO/Virgo/KAGRA S251112cm: WFST follow-up observations and preliminary results
  17. GRB 251116C: Swift-XRT observations
  18. GRB 251116D: Glowbug gamma-ray detection
  19. EP251023a: Assy AZT-20 optical observations
  20. GRB 251116D: AstroSat CZTI detection
  21. GRB 251116C: SVOM/VT optical upper limit
  22. LIGO/Virgo/KAGRA S251116en: Identification of a GW compact binary merger candidate
  23. LIGO/Virgo/KAGRA S251112cm: Observations with the NSF-DOE Vera C. Rubin Observatory
  24. GRB 251116B: LCO optical upper limits
  25. GRB 251116C: LCO optical upper limits
  26. GRB 251116C: SVOM detection of a burst
  27. GRB 251116B: SVOM detection of a burst
  28. LIGO/Virgo/KAGRA S251112cm: GRANDMA observations of the skymap
  29. LIGO/Virgo/KAGRA S251112cm: AT2025adht follow-up at Maidanak observatory by GRANDMA
  30. LIGO/Virgo/KAGRA S251112cm: NED Galaxies in the 4-Update Localization Volume
  31. GRB 251113A: Glowbug gamma-ray detection
  32. GRB 251113A: AstroSat CZTI detection
  33. GRB 251112A: Swift-BAT refined analysis
  34. Konus-Wind detection of GRB 251108C
  35. Konus-Wind detection of GRB 251103A
  36. LIGO/Virgo/KAGRA S251112cm: ATLAS targeted observations of the skymap
  37. LIGO/Virgo/KAGRA S251112cm: Swift XRT observations, 20 X-ray sources
  38. LIGO/Virgo/KAGRA S251112cm: Candidates from the Zwicky Transient Facility
  39. LIGO/Virgo/KAGRA S251112cm: TROVE Vetting of TNS Candidates
  40. GRB 251111A: SVOM/ECLAIRs refined analysis
  41. GRB 251025B: SVOM/ECLAIRs refined analysis
  42. LIGO/Virgo/KAGRA S251112cm: ATLAS pre-detections of AT2025adgp and AT2025adgq
  43. GRB 251108C: AstroSat CZTI detection
  44. GRB 251112B: MAXI/GSC detection
  45. LIGO/Virgo/KAGRA S251112cm: Coverage and upper limits from MAXI/GSC observations
  46. LIGO/Virgo/KAGRA S251112cm: Initial GOTO-South observations
  47. GRB 251108B: Glowbug gamma-ray detection
  48. Swift Trigger 1413695: a possible GRB 251112A
  49. LIGO/Virgo/KAGRA S251112cm: NED Galaxies in the 3-Initial Localization Volume
  50. LIGO/Virgo/KAGRA S251112cm: Identification of a GW compact binary merger candidate
  51. GRB 251106B: Glowbug gamma-ray detection of a likely short burst
  52. GRB 251111A: Swift-XRT observations
  53. GRB 251111A: EP-FXT counterpart detection
  54. GRB 251013C: Chandra X-ray observations and jet break detection
  55. GRB 251111A: KAIT optical upper limit
  56. GRB 251111A: SVOM/COLIBRÍ (FM-GFT) optical counterpart detection
  57. GRB 251103B: Swift-BAT refined analysis
  58. GRB 251106A: Swift/UVOT Upper Limits
  59. LIGO/Virgo/KAGRA S251108fi: DDOTI Optical Candidate
  60. GRB 251105A: AstroSat CZTI detection
  61. LIGO/Virgo/KAGRA S251108fi: One counterpart neutrino candidate from IceCube neutrino searches
  62. LIGO/Virgo/KAGRA S251108fi: Identification of a GW compact binary merger candidate
  63. GRB 251102B: SVOM/GRM observation
  64. LIGO/Virgo/KAGRA S251108dn: Identification of a GW compact binary merger candidate
  65. The EP-WXT trigger 01709248051 is likely a flaring star
  66. IPN triangulation of GRB 251105B (possible sGRB with EE)
  67. GRB 251106A: SVOM/COLIBRÍ (FM-GFT) fading of the optical counterpart
  68. GRB 251106A: Kilonova-Catcher optical upper limit
  69. Fermi GBM Sub-Threshold Detection of GRB 251106A
  70. GRB 251106A: SVOM/COLIBRÍ (FM-GFT) detection of a likely optical counterpart
  71. GRB 251106A: SVOM detection of a burst
  72. GRB 251103B: AstroSat CZTI detection
  73. GRB 251025C: TERI Gamma-ray detection
  74. GRB 251016B: TERI Gamma-ray detection
  75. GRB 251016A: TERI Gamma-ray detection of a short burst
  76. GRB 250920C: TERI Gamma-ray detection
  77. EP251102a: Xinglong 2.16-m clear-band observations of the optical counterpart
  78. GRB 251104A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  79. GRB 251105B: AstroSat CZTI detection of a short burst with extended emission
  80. GRB 251023A: SVOM/ECLAIRs detection of a burst through targeted search
  81. LIGO/Virgo/KAGRA S251105aj: Identification of a GW compact binary merger candidate
  82. GRB 251103B: Fermi GBM observation
  83. GRB 251104A: SVOM detection of a burst
  84. GRB 251103A: Xinglong 2.16m optical detection
  85. GRB 251103A: KAIT optical observations
  86. GRB 251013C: 7DT detection and Medium-band SED of Afterglow
  87. GRB 251103B: MITSuME Akeno optical upper limits
  88. LIGO/Virgo/KAGRA S251103f: Identification of a GW compact binary merger candidate
  89. EP251102a: NIR observations with WINTER
  90. GRB 251103A: J-band detection with WINTER
  91. GRB 251103A: Kilonova-Catcher optical afterglow detection
  92. GRB 251103B: Swift detection of a burst
  93. GRB 251103A: Fermi GBM Observation
  94. GRB 251103A: Swift-XRT afterglow detection
  95. GRB 251103A: SVOM/COLIBRÍ (FM-GFT) optical observations
  96. GRB 251103A: LCO optical observation
  97. EP251102.890: COLIBRÍ optical counterpart candidate
  98. GRB 251103A: GOTO optical afterglow detection
  99. GRB 251102A: AstroSat CZTI detection
  100. GRB 251026A: SVOM/COLIBRÍ (FM-GFT) confirmation of the optical counterpart

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