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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"

43954 results found.

  1. LIGO/Virgo G298048: Possible features in the spectrum of GW counterpart SSS17a
  2. LIGO/Virgo G298048: GROND photometry of candidate optical counterpart reveals brightening in the NIR
  3. LIGO/Virgo G298048: Additional Swope Observations of SSS17a
  4. LIGO/VIRGO G298048: ePESSTO optical spectra of the candidate optical/NIR counterpart of the gravitational wave G298048 in NGC4993.
  5. LIGO/Virgo G298048: Rapid Evolution of Possible Counterpart
  6. LIGO/Virgo G298048: Observed fading of optical counterpart SSS17a
  7. LIGO/Virgo G298048: Continued observation for DLT17ck
  8. LIGO/VIRGO G298048: Expansion Velocity of SSS17a Consistent With Relativistic Merger Ejecta
  9. LIGO/Virgo G298048: optical spectral energy distribution of SSS17a
  10. LIGO/Virgo G298048: prior photometry from VISTA Hemisphere Survey
  11. LIGO/Virgo G298048: Archival 2MASS and Spitzer non-detections of the potential LIGO EM counterpart SSS17a
  12. LIGO/Virgo G298048: ATCA upper limits on radio emission from optical source SSS17a in NGC 4993
  13. GRB 170818A: Fermi GBM detection
  14. LIGO/Virgo G298048: Continued Swift UV and X-ray Monitoring of SSS17a
  15. LIGO/Virgo G298048: Archival VLA observations
  16. LIGO/Virgo G298048: New MASTER observations of the OT in NGC 4993
  17. LIGO/Virgo G298048: UPDATE on IceCube neutrino candidates --- no coincidence with newest GW skymap
  18. LIGO/Virgo G298048: Correction to Swope photometry announced in LVC GCN 21529
  19. LIGO/Virgo G298048: Moderate dimming or no brightening of the optical counterpart candidate?
  20. LIGO/Virgo G298048: Brightening of Possible Counterpart
  21. LIGO/Virgo G298048: AGILE-GRID analysis of the potential counterpart field
  22. LIGO/Virgo G298048: ASKAP search for fast radio bursts
  23. LIGO/Virgo G298048: Subaru HSC z-band photometry of the possible optical counterpart
  24. LIGO/Virgo G298048: SkyMapper uvgri photometry of the candidate in NGC 4933
  25. LIGO/Virgo G298048: ATCA detection of a radio source coincident with NGC 4993
  26. LIGO/Virgo G298048: TZAC TAROT Reunion (TRE) observations
  27. LIGO/Virgo G298048: Likelihood of SSS17a Being an Unrelated Extragalactic Transient in NGC 4993
  28. LIGO/Virgo G298048: REM optical/NIR observations
  29. LIGO/Virgo G298048, Fermi GBM trigger 524666471/170817.529: MAXI/GSC observations
  30. LIGO/Virgo G298048: HCT observations
  31. LIGO/Virgo G298048: Pan-STARRS detections and izy photometry of the possible optical/NIR counterpart in NGC4993
  32. LIGO/Virgo G298048: Gemini-South Near-Infrared Photometry of the Optical Transient Candidate
  33. LIGO/Virgo G298048: Magellan g-band Imaging of the Potential Optical Counterpart Associated with NGC 4993
  34. LIGO/VIRGO G298048: Swift UVOT detection and XRT upper limits
  35. LIGO/Virgo G298048: VLA Refined Analysis
  36. LIGO/VIRGO G298048: Magellan Optical Spectrum of the Potential Optical Counterpart Associated with NGC 4993
  37. LIGO/Virgo G298048: MASTER observations of the NGC 4993
  38. LIGO/Virgo G298048: VLA Detection
  39. LIGO/Virgo G298048: VISTA/VIRCAM detection of candidate counterpart
  40. LIGO/Virgo G298048: Galaxy-Targeted Optical Followup With Las Cumbres Observatory
  41. LIGO/Virgo G298048: Optical Candidate Shows No Evidence for Previous Activity in Archival SkyMapper Transient Survey Data
  42. LIGO/VIRGO G298048: The Potential Optical Counterpart in NGC 4993 Has Afterglow-Like Colors
  43. GRB 170817B: Fermi GBM detection
  44. LIGO/Virgo G298048: DLT40 follow-up observation
  45. LIGO/Virgo G298048: Las Cumbres Observatory Detection of The Possible Optical Counterpart in NGC 4993
  46. LIGO/Virgo G298048: ATCA observations of candidate host galaxies
  47. LIGO/Virgo G298048: Inspection of archival HST data at the position of the potential optical counterpart
  48. LIGO/Virgo G298048: Nearby Galaxies in the Localization Volume using the updated sky map computed using LALInference
  49. LIGO/Virgo G298048 : Fermi-LAT search for a high-energy gamma-ray counterpart
  50. LIGO/Virgo G298048: Optical Candidate Shows No Evidence for Previous Activity in Archival ASAS-SN Data
  51. LIGO/Virgo G298048: REM optical/NIR observations of candidate in NGC 4993
  52. LIGO/Virgo G298048: DLT40 optical candidate
  53. LIGO/Virgo G298048: DECam optical candidate
  54. LIGO/Virgo G298048: Potential optical counterpart discovered by Swope telescope
  55. LIGO/Virgo G298048 - Update on Fermi/GBM GRB 170817A Analysis
  56. LIGO/Virgo G298048: Updated sky map from gravitational-wave data
  57. LIGO/Virgo G298048: AGILE GRID observations
  58. LIGO/Virgo G298048: AGILE MCAL observations
  59. LIGO/Virgo G298048: Swift/BAT data search
  60. LIGO/Virgo G297595: Pierre Auger Observatory neutrino follow-up
  61. LIGO/Virgo G298048 ANTARES search
  62. LIGO/Virgo G298048: Nearby Galaxies in the Localization Volume with Face-on Assumption
  63. GRB 170817A: Fermi GBM detection
  64. LIGO/Virgo G298048: Nearby Galaxies in the Localization Volume
  65. LIGO/Virgo G298048: Insight-HXMT observations
  66. IPN Triangulation of GRB 170816A (short/hard)
  67. LIGO/Virgo G298048: Potential host galaxies from the GLADE catalog
  68. LIGO/Virgo G298048: IPN triangulation of Fermi/GBM trigger 524666471/170817529
  69. LIGO/Virgo G298048: Astrosat CZTI upper limits
  70. LIGO/Virgo G298048: Further analysis of a binary neutron star candidate with updated sky localization
  71. LIGO/Virgo G297595: Liverpool Telescope observations of MASTER transients
  72. LIGO/Virgo G298048: COINCIDENT IceCube neutrino candidate with Fermi GBM trigger 524666471/170817529
  73. LIGO/Virgo G298048: correction to the luminosity distance reported in GCN 21509
  74. LIGO/Virgo G298048: Identification of a binary neutron star candidate coincident with Fermi GBM trigger 524666471/170817529
  75. LIGO/Virgo G298048: FOUND COINCIDENT IceCube neutrino observation
  76. LIGO/Virgo G298048: INTEGRAL detection of a prompt gamma-ray counterpart
  77. LIGO/Virgo G298048: Fermi GBM trigger 170817.529 and LIGO single IFO trigger
  78. LIGO/Virgo G298048: Fermi GBM trigger 524666471/170817529: LIGO/Virgo Identification of a possible gravitational-wave counterpart
  79. GRB 170816A: Fermi GBM detection
  80. LIGO/Virgo G297595: Swift-XRT sources
  81. GRB 170805A: AstroSat CZTI detection
  82. LIGO/Virgo G296853 TZAC TAROT observations
  83. LIGO/Virgo G297595: Konus-Wind observations
  84. LIGO/Virgo G297595: MASTER MASTER Bright PSN detection in error-box
  85. LIGO/Virgo G297595: INAF VST-ESO PARANAL observations
  86. LIGO/Virgo G296853: Pierre Auger Observatory neutrino follow-up
  87. LIGO/Virgo G297595: REM optical/NIR observations
  88. LIGO/Virgo G297595 : MAXI/GSC observations
  89. LIGO/Virgo G297595: Updated localization from LIGO and Virgo data
  90. GRB 170810A: VLA Detection
  91. GRB 170813A: Fermi GBM observation
  92. Fermi GBM trigger 524493492/170815526 is not a GRB
  93. LIGO/Virgo G297595: Correction to luminosity distance stated in GCN 21474
  94. LIGO/Virgo G297595: Pan-STARRS coverage and transients over the first 5hrs
  95. LIGO/Virgo G297595: Insight-HXMT observations
  96. LIGO/Virgo G297595: Nearby Galaxies in the Localization Volume
  97. LIGO/Virgo G297595: Fermi GBM Observations
  98. LIGO/Virgo G297595: Swift/BAT data search
  99. LIGO/Virgo G297595: AGILE GRID observations
  100. LIGO/Virgo G297595 : Fermi-LAT search for high-energy gamma-ray counterpart

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