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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.

Advanced Search Examples (click to copy):

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

43959 results found.

  1. GRB 170903A: Enhanced Swift-XRT position
  2. GRB 170903A: Swift-BAT refined analysis
  3. GRB 170903A: Nanshan optical upper limit
  4. GRB 170903A: Swift-XRT observations
  5. GRB 170903A: Swift detection of a burst
  6. Swift Triggers on MAXI J1535-571
  7. Swift Trigger 770431 (GRB 170902A) is a not a GRB
  8. GRB 170902A: Enhanced Swift-XRT position
  9. LIGO/Virgo G297595: DECam observations of BBH merger region of interest
  10. GRB 170902A: Swift detection of a burst or possible Galactic transient
  11. LIGO/Virgo G298048: Chandra monitoring of the X-ray emission from SSS17a
  12. LIGO/Virgo G298048: Continued X-ray monitoring and X-ray detection of GW170817 [erratum]]
  13. LIGO/Virgo G298048: AGILE-GRID analysis of data contemporary to X-ray emission from SSS17a in NGC4993
  14. LIGO/Virgo G298048
  15. LIGO/Virgo G299232/PGWB170825.55: MASTER archive images of the SIWFT/UVOT and MASTER OT J033744.97+723159.0 in NGC1343 galaxy before 25
  16. LIGO/Virgo G298048: Hubble Space Telescope observations
  17. LIGO/Virgo G299232: XSNAOC spectral observation of MASTER OTJ033744.97+723159.0
  18. LIGO/Virgo G298048: Possible Plateau in Ks band revealed by continued Gemini-South observations
  19. LIGO/Virgo G298048: Continued Gemini South observations
  20. GRB 170831A: Fermi GBM detection
  21. GRB 170830A: Fermi GBM observation
  22. Konus-Wind observation of GRB 170827B
  23. Konus-Wind observation of GRB 170826A
  24. GRB 170830A: Astrosat CZTI detection
  25. LIGO/Virgo G299232: GRAWITA Asiago optical observations
  26. LIGO/Virgo G299232: continued WHT observations of the field of SwiftJ014008.5+343403.6
  27. LIGO/Virgo G298936: PIRATE observations
  28. LIGO/Virgo G299232 ANTARES search (2)
  29. LIGO/Virgo G298048: GMRT Follow-up of SSS17a at 1.4 GHz
  30. Konus-Wind observation of GRB 170826B
  31. LIGO/Virgo G299232: GRAWITA Campo Imperatore optical observations
  32. LIGO/Virgo G298048: Discovery of X-ray emission from SSS17a in NGC4993
  33. GRB 170830A: iTelescope optical observations
  34. LIGO/Virgo G298048: European VLBI Network (EVN) upper limit on 5 GHz compact emission from SSS17a
  35. LIGO/Virgo G299232: SVOM/2.16-m Optical Telescope Observations of Swift UVOT Transient
  36. GRB 170830A: MAXI/GSC detection
  37. LIGO/Virgo G298048: OVRO 40m telescope follow-up
  38. LIGO/Virgo G299232: HAWC follow-up
  39. LIGO/Virgo G299232: Further Swift/UVOT Observations of Optical Transient SwiftJ014008.5+343403.6
  40. LIGO/Virgo G299232 : RATIR Optical and NIR Observations of Swift UVOT source
  41. LIGO/Virgo G299232: WHT non-detection u-band optical transient
  42. LIGO/Virgo G299232: Liverpool Telescope observations
  43. LIGO/Virgo G299232: observations of the optical Transient Discovered by Swift/UVOT
  44. IPN Triangulation of GRB 170826B
  45. LIGO/Virgo G299232: PIRATE observations of MASTER OT J033744.97+723159.0
  46. LIGO/Virgo G298936: Updated localization from parameter estimation on LIGO and Virgo data
  47. LIGO/Virgo G298048: ALMA upper limits on 98 GHz emission from SSS17a
  48. LIGO/Virgo G299232/PGWB170825.55: early MASTER observations of the Swift UVOT source position
  49. LIGO/Virgo G296853: PIRATE observations
  50. LIGO/Virgo G298048: ALMA observations
  51. LIGO/Virgo G298048: Konus-Wind observations
  52. LIGO/Virgo G299232: GRAWITA Asiago/Copernico Telescope observations
  53. LIGO/Virgo G298048: Zadko Telescope 7 day observations of the OT candidate SSS17a/DLT17ck
  54. LIGO/Virgo G299232: COATLI Observations of MASTER OT J033744.97+723159.0
  55. LIGO/Virgo G299232 : MAXI/GSC observations
  56. LIGO/Virgo G298048: Further ATCA follow-up of SSS17a in NGC 4993
  57. GRB 170826B: Insight-HXMT detection
  58. LIGO/Virgo G299232: Continued observation of the transient near NGC 1343
  59. LIGO/Virgo G299232: WHT spectrum of MASTER OT J033744.97+723159.0
  60. LIGO/Virgo G299232/PGWB170825.55: MASTER OT J033744.97+723159.0 inside 25m isophota of the NGC1343 galaxy is reddening
  61. IPN Triangulation of GRB 170827B (short)
  62. IPN Triangulation of GRB 170826A (short)
  63. LIGO/Virgo G299232: Optical Transient Discovery by Swift/UVOT
  64. LIGO/Virgo G298936: HAWC follow-up
  65. LIGO/Virgo G299232 TZAC/TAROT observations
  66. GRB 170827A: Swift-XRT refined Analysis
  67. GROND observations of GRB170827A
  68. GRB 170827A: ePESSTO NTT afterglow candidate
  69. GRB 170823A: TAROT Calern observatory optical observations
  70. LIGO/Virgo G299232: OVRO-LWA simultaneous low frequency radio observations of localization region
  71. LIGO/Virgo G299232: LOFAR follow-up
  72. GRB 170827A, Swift-BAT refined analysis
  73. LIGO/Virgo G299232: Transient near NGC 1343 has a somewhat blue r-i color
  74. GRB 170827A: Swift/UVOT Upper Limits
  75. GRB 170827A: REM optical/NIR observations
  76. LIGO/Virgo G299232/PGWB170825.55: MASTER OTJ033744.97+723159.0 off set from NGC1343 galaxy
  77. LIGO/Virgo G299232/PGWB170825.55: MASTER Global-Net OT inside NGC1343 discovery
  78. GRB 170827A: Swift detection of a burst
  79. GRB 170826B: Fermi GBM detection
  80. LIGO/Virgo G299232: CALET Observations
  81. GRB 170826A: Fermi GBM detection
  82. LIGO/Virgo G298936: Astrosat CZTI upper limits
  83. LIGO/Virgo G299232: XRT Rank 2 source is not real
  84. LIGO/Virgo G299232: Astrosat CZTI upper limits
  85. LIGO/VIRGO G299232: Fermi GBM Observations
  86. LIGO/Virgo G299232 : Fermi-LAT search for high-energy gamma-ray counterpart
  87. LIGO/Virgo G298389: HAWC follow-up
  88. LIGO/Virgo G298048: uGMRT Follow-up of SSS17a at 400 MHz and 1.4 GHz
  89. LIGO/Virgo G299232: Nearby Galaxies in the Localization Volume
  90. LIGO/Virgo G298936: CALET Observations
  91. GRB 170820A CALET Gamma-Ray Burst Monitor detection
  92. LIGO/Virgo G299232: Swift/BAT data search
  93. LIGO/VIRGO G298048: INAF VST-ESO PARANAL observations of NGC4993
  94. GRB 170822A: AstroSat CZTI detection
  95. LIGO/Virgo G299232: AGILE GRID observations
  96. LIGO/Virgo G299232: AGILE MCAL detection of a short gamma-ray candidate
  97. LIGO/Virgo G299232: INTEGRAL search for a prompt gamma-ray counterpart
  98. LIGO/Virgo G299232: COINCIDENT IceCube neutrino observation UPDATE
  99. LIGO/Virgo G296853: VLT observations by GLGW Hunters
  100. LIGO/Virgo G299232 ANTARES search

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