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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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10955 results found.

  1. GRB 251126A: Mondy and SAO RAS optical observations
  2. GRB 251126A : MITSuME Akeno optical afterglow candidate detection
  3. GRB 251125B: COLIBRÍ further observations and photometric redshift upper limit of z < 3
  4. EP251124b follow-up observation by EP-FXT
  5. EP251124b: NOT r- and z-band optical upper limits
  6. Fermi GRB 251125B : MASTER OT J155558.56+581224.1 optical counterpart discovery
  7. EP251124a: Xinglong GWAC-F60A optical observation
  8. EP251124a (EP-WXT trigger 01709248862) is triggered by the known source AWM 7
  9. EP251124a: NOT r- and z-band optical upper limits
  10. LIGO/Virgo/KAGRA S251112cm: AT 2025adht Kinder follow-up observations
  11. EP251124a: Optical upper limit with Kinder observations
  12. LIGO/Virgo/KAGRA S251105aj: SVOM/VT optical observations and preliminary results on SVOM J2320.0-2901
  13. LIGO/Virgo/KAGRA S251105aj: EP-FXT follow-up observations and preliminary results on SVOM J2320.0-2901
  14. EP251124a: Einstein Probe detection of an X-ray transient
  15. GRB 251122A / EP251122a: Xinglong 2.16m optical observation
  16. EP251122a / GRB 251122A: optical counterpart candidate with Kinder observations
  17. EP251118a: Continued Optical Detection with Kinder observations
  18. LIGO/Virgo/KAGRA S251105aj: SVOM/ECLAIRs detection of a high-energy transient SVOM J2320.0-2901 through targeted search
  19. GRB 251103A: SVOM/ECLAIRs and SVOM/GRM joint refined analysis
  20. EP251118a: Optical detection with Kinder observations
  21. EP-WXT trigger 01709248403: confirmation of a stellar flare by SVOM/VT
  22. LIGO/Virgo/KAGRA S251112cm: SVOM/VT optical observations and preliminary results
  23. EP251118a / GRB 251118C: SVOM/VT optical observation
  24. GRB 251118C: Swift/BAT rates detection of a burst with a possible association with EP 251118A
  25. EP251118A / GRB 251118C : MASTER optical counterpart observations
  26. GRB 251013C: Koshka, SAO RAS, Mondy, and CrAO optical observations, possible SN detection
  27. GRB 251117A: Fermi-LAT detection
  28. GRB 251116C: Swift/BAT arcminute localization of a burst
  29. GRB 251116B: SVOM/VT optical upper limit
  30. EP251023a: Assy AZT-20 optical observations
  31. EP251023a: UAFO and AbAO optical observations
  32. The EP-WXT trigger 01709247588: more evidence of flaring star from Mondy optical observations
  33. GRB 251116C: SVOM/VT optical upper limit
  34. GRB 251025B: further Mondy optical observations
  35. GRB 251111A: Mondy optical upper limit
  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: TROVE Vetting of TNS Candidates
  39. LIGO/Virgo/KAGRA S251112cm: ATLAS pre-detections of AT2025adgp and AT2025adgq
  40. LIGO/Virgo/KAGRA S251112cm: Detection of two young transients by BlackGEM/MeerLICHT: AT2025adgp and AT2025adgq
  41. GRB 251112B: MAXI/GSC detection
  42. LIGO/Virgo/KAGRA S251112cm: Coverage and upper limits from MAXI/GSC observations
  43. GRB 251111A: SVOM/VT optical observations with X-band data
  44. GRB 251111A: SVOM/COLIBRÍ (FM-GFT) optical counterpart detection
  45. GRB 251106A: Swift/BAT arcminute localization of a burst
  46. GRB 251106A: MASTER optical observations
  47. GRB 251104A: SVOM detection of a burst
  48. GRB 251103B: MITSuME Akeno optical upper limits
  49. GRB 250926B: VZLUSAT-2 detection
  50. GRB 250926A: VZLUSAT-2 detection
  51. GRB 250925A: VZLUSAT-2 detection
  52. GRB 251026A/EP251026a: SVOM/VT optical counterpart
  53. GRB 251028B: CALET Gamma-Ray Burst Monitor detection
  54. GRB251026B: PRIME H-band upper limit
  55. GRB 251028A: MAXI/GSC detection
  56. GRB 251022A: SVOM/GRM observation
  57. GRB 251017A: Mondy AZT-33IK and Koshka Zeiss-1000 optical observations
  58. GRB 251023B / EP251023b: Mondy optical upper limit
  59. GRB 251017A: INASAN-Kislovodsk optical observations
  60. GRB 251026A: Mondy optical upper limit
  61. GRB 251025B: Mondy optical observations
  62. GRB 251025B: VLT/MUSE spectroscopic redshift z = 2.003
  63. EP251023a: Mondy optical observations
  64. GRB 251025C: CALET Gamma-Ray Burst Monitor detection
  65. GRB 251025B: MASTER OT detection
  66. GRB 251025A (sb25102501): Likely a stellar flare by SVOM/VT
  67. EP251023b/GRB 251023B : Einstein Probe detection of a fast X-ray transient
  68. GRB 251023C: CALET Gamma-Ray Burst Monitor detection
  69. GRB 251022A: Fermi GBM Observation
  70. GRB 251023B: CALET Gamma-Ray Burst Monitor detection
  71. GRB 251013C: ISON-Castelgrande observatory optical observations
  72. GRB 251022A: MASTER OT detection
  73. GRB 251023B / MAXI J0451+122: MAXI/GSC detection
  74. EP251023a: Einstein Probe detection of an X-ray transient
  75. GRB 251022A: Fermi-LAT detection
  76. GRB 250911A: MAXI/GSC detection
  77. GRB 251017A : RAPAS follow-up observations
  78. GRB 251017A: VLT/MUSE spectroscopic redshift z = 4.327
  79. GRB 251018A: MASTER OT detection
  80. GRB 251017A: SVOM/VT optical observation
  81. GRB 251017A : MITSuME Akeno optical afterglow candidate detection
  82. Swift Trigger 1404295 is not a GRB
  83. GRB 251016A: CALET Gamma-Ray Burst Monitor detection
  84. GRB 251016B: CALET Gamma-Ray Burst Monitor detection
  85. GRB 251014D: Swift-BAT refined analysis
  86. GRB 251013C: VLA detection
  87. GRB 251014B: PRIME J-band upper limit
  88. GRB 251013C: SVOM/ECLAIRs refined analysis
  89. Swift Trigger 1404295: possible GRB 251015A
  90. GRB 251014B: Swift/UVOT Upper Limits
  91. GRB 251014D: Swift/UVOT Upper Limits
  92. GRB 251011B: SVOM/VT optical upper limit
  93. GRB 251014D: Swift detection of a burst
  94. GRB 251014A: PRIME near-infrared upper limits
  95. GRB 251013C: Osservatorio Astronomico "Nastro Verde" optical observations: detection of an bright optical counterpart
  96. GRB 251013C: Fermi GBM Observation
  97. GRB 251013C NUTTelA-TAO / BSTI Early Measurements
  98. GRB 251013A: CALET Gamma-Ray Burst Monitor detection
  99. GRB 251013C: J band observations by SYSU 80cm infrared telescope
  100. GRB 251013C: ALMA detection

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