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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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').

823 results found.

  1. IceCube-201114A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  2. VLASS identifies possible radio counterparts to IceCube-201115A, including a bright BL Lac candidate
  3. Swift Trigger 1005428: Detection of SGR 1830-0645
  4. Swift Trigger 1004219: Detection of SGR 1830-0645
  5. IceCube-201021A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  6. IceCube-201014A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  7. SGR 1830-0645: Swift/UVOT Upper Limits
  8. GRB 201011A: Fermi GBM detection of a likely Long GRB in the direction of SGR 1830-0645
  9. Fermi trigger No 624139481: AGILE detection
  10. SGR 1830-0645: pre-discovery detection in Swift/BAT
  11. SGR 1830-0645 / GRB 201010A: 1.5m OSN optical upper limit
  12. SGR 1830-0645: Swift-BAT refined analysis
  13. SGR 1830-0645 / GRB 201010A: Kitab optical non-detection
  14. Swift detection of a new SGR 1830-0645 or a short GRB 201010A
  15. IceCube-201007A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  16. IceCube-200926B: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  17. IceCube-200929A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  18. Fermi-LAT Gamma-ray Observations of IceCube-200926B
  19. IceCube-200921A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  20. IceCube-200916A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  21. Fermi-LAT Gamma-ray Observations of IceCube-200916A
  22. IceCube-200911A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  23. IceCube-200806A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  24. Fermi-LAT Gamma-ray Observations of IceCube-200806A
  25. AX J1846.4-0258: Swift-BAT refined analysis
  26. Swift Detection of an SGR-like flare from AX J1846.4-0258
  27. Fermi GBM trigger 616776657/200718619 is not a GRB
  28. Trigger 980513: Swift detection of SGR Swift J1818.0-1607
  29. Updated catalog of X-ray bursts of SGR J1935+2154 from Insight-HXMT observations
  30. IceCube-200615A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  31. IceCube-200614A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  32. 1RXS J1708−4009: Swift-BAT refined analysis
  33. Swift detection of an SGR-like burst from 1RXS J1708−4009
  34. Fermi-LAT Gamma-ray Observations of IceCube-200530A
  35. IceCube-200530A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  36. Fermi-LAT Gamma-ray Observations of IceCube-190523A
  37. Swift J1818.0-1607: BOOTES-3/YA optical upper limit
  38. Swift Detection of a burst from SGR Swift J1818.0-1607
  39. AGILE detection of a burst from SGR 1935+2154 on May 10, 2020
  40. Fermi-LAT Gamma-ray Observations of IceCube-200512A
  41. SGR 1935+2154: AstroSat CZTI detection
  42. IceCube-200512A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  43. Insight-HXMT's continued observation plan for SGR J1935+2154
  44. Konus-Wind observation of SGR 1935+2154 activity on 2020 May 10
  45. IPN triangulation of a bright burst from SGR 1935+2154 on 2020-05-10 at 06:12 UT
  46. FRB/X-ray bursts from SGR 1935+2154: No Neutrino Counterpart in ANTARES data
  47. Swift Detection of a burst from SGR Swift J1818.0-1607
  48. Insight-HXMT detection of a short bright burst from SGR 1935+2154
  49. AGILE detection of a short and hard X-ray burst possibly related to SGR 1935+2154
  50. Geocentric time correction for Insight-HXMT detection of the x-ray counterpart of the FRB by CHIME and STARE2 from SGR 1935+2154
  51. Insight-HXMT X-ray and hard X-ray upper limits to the radio burst detected by FAST from SGR 1935+2154
  52. No optical bursts detected from SGR J1935+2154 by 24 fps observations with Tomo-e Gozen
  53. Insight-HXMT X-ray and hard X-ray detection of the double peaks of the Fast Radio Burst from SGR 1935+2154
  54. Fermi GBM observation of a flare from the magnetar SGR 1806-20
  55. Trigger 968731: Swift detection of SGR1806-20
  56. Fermi GBM trigger 200429866/609886052 is not a GRB
  57. SGR 1935+2154: MASTER optical observations
  58. Konus-Wind observation of hard X-ray counterpart of the radio burst from SGR 1935+2154
  59. SGR 1935+2154: INTEGRAL hard X-ray counterpart of radio burst
  60. Konus-Wind observation of a very intense bursting activity of SGR 1935+2154
  61. A Forest of Bursts from SGR 1935+2154
  62. SGR 1935+2154: AstroSat CZTI detections
  63. high bursting activity of SGR 1935+2154: CGBM observations
  64. SGR 1935+2154 the Insight-HXMT observation plan
  65. SGR 1935+2154: MAXI/GSC detection
  66. Fermi GBM observation of a bright flare from magnetar SGR 1935+2154
  67. Swift detection of multiple bursts from SGR 1935+2154
  68. IceCube-200425A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  69. Konus-Wind observation of a bright burst from SGR 1935+2154
  70. GRB 200415A (possible magnetar Giant Flare in Sculptor Galaxy): INTEGRAL observations
  71. IPN Triangulation of a bright burst from SGR 1935+2154
  72. bright SGR burst detected by CALET Gamma-Ray Burst Monitor
  73. IceCube-200421A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  74. Konus-Wind observation of GRB 200415A (a magnetar Giant Flare in Sculptor Galaxy?)
  75. Konus-Wind observation of a bright burst from SGR 1935+2154
  76. Fermi-LAT Gamma-ray Observations of IceCube-200410A
  77. IceCube-200410A: Possible associated excess in INTEGRAL SPI-ACS prompt observation
  78. SGR 1935+2154: Fermi GBM observation
  79. IPN Triangulation of a bright burst from SGR 1935+2154
  80. LIGO/Virgo S200316bj: No counterpart candidates in INTEGRAL SPI-ACS, and IBIS prompt observation
  81. SGR Swift J1818.0-1607: Swift-BAT refined analysis
  82. SGR Swift J1818.0-1607: BOOTES-4/MET optical limit
  83. Swift-BAT trigger 960986: Swift detection of a new SGR Swift J1818.0-1607
  84. LIGO/Virgo S200311bg: No counterpart candidates in INTEGRAL SPI-ACS,prompt observation
  85. LIGO/Virgo S200302c: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  86. Fermi-LAT Gamma-ray Observations of IceCube-200227A
  87. IceCube-200227A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  88. LIGO/Virgo S200225q: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  89. LIGO/Virgo S200224ca: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  90. LIGO/Virgo S200219ac: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  91. LIGO/Virgo S200213t: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  92. LIGO/Virgo S200208q: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  93. Re-classification of Fermi GBM triggers 200203137, 200203156/GRB200203A and 200203861
  94. LIGO/Virgo S200129m: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  95. LIGO/Virgo S200128d: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  96. IceCube-200120A: no counterpart candidates in INTEGRAL SPI-ACS and,IBIS prompt observation
  97. IceCube-200117A: no counterpart candidates in INTEGRAL SPI-ACS and,IBIS prompt observation
  98. LIGO/Virgo S200114f: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  99. LIGO/Virgo S200112r: upper limits from AGILE/GRID observations
  100. Fermi-LAT ANTARES coincidence: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation

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