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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').
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"

25006 results found.

  1. GRB030528, BVRI field photometry
  2. GRB030329, SPM optical observations
  3. GRB030528: Chandra TOO Planned
  4. GRB030528(=H2724): Revised SXC Localization
  5. GRB 030528 Bisei optical observation
  6. GRB030528 (H2724): A long GRB localized by HETE
  7. GRB 030329: Correction to GCN 2254
  8. GRB 030329: Optical Observations
  9. GRB 030528 (=H2724) Kyoto optical observation
  10. GRB 030416: Optical Observations
  11. GRB 030329 Optical Observations
  12. GRB030329: XMM-Newton observation
  13. GRB 021004: HST observations
  14. GRB030324: Further Observations of the Candidate Optical Afterglow
  15. GRB030519B (=H2716): Peak Fluxes, Fluences, and Energy Spectrum
  16. IPN triangulation of GRB030519B=H2716 (small error box)
  17. HETE GRB030329, correction to Rc Observations in Loiano
  18. GRB 030329: Optical limit (contemporaneous imaging)
  19. IPN triangulation of GRB030509 (small errror box)
  20. GRB030329, BVRI photometry
  21. GRB030429, refiend optical brightness
  22. GRB 030329: Optical limit (contemporaneous photography)
  23. GRB030418, BVRcIc field photometry
  24. GRB030429, BVRcIc field photometry
  25. GRB030429 (=H2695): A Long GRB Localized by the HETE WXM and SXC
  26. XRF030416 (=U10897): An X-Ray Flash Localized by the HETE WXM
  27. GRB030329: RTT150 optical observations and upper limit for a host
  28. GRB030501, optical observation
  29. GRB030501 triangulation (correction to GCN 2194)
  30. GRB030329: RTT150 optical observations and upper limit for a host
  31. GRB 030429: redshift from VLT spectroscopy
  32. GRB030501B triangulation (single error box)
  33. GRB 030329, BVRI photometry
  34. GRB030429: Optical Observations
  35. GRB030501: TAROT candidate afterglow present in archival images
  36. GRB 030429: confirmation of afterglow candidate
  37. GRB 030329 Oprical observations in Rozhen observatory
  38. SNeIa AS THE POSSIBLE PROGENITORS OF SHORT-DURATION GRBs.
  39. IPN triangulation of GRB030425 (single error box)
  40. GRB 030329, the review of the sky area in plate archive (1950-1998)
  41. GRB 030329: optical spectropolarimetry at VLT
  42. GRB 030329: wide-field photograph by R. Tamura 1 hr after the burst
  43. GRB030329: optical polarization
  44. IPN triangulation of GRB030422 (two large error boxes)
  45. GRB030329, optical observation
  46. MASTER:optical observations GRB030418
  47. MASTER:optical observations probable GRB030414
  48. GRB030418: Kiso near infrared observations
  49. GRB 030418: Optical afterglow
  50. OT GRB 030329: early UBVRcIc spectral evolution
  51. OT GRB 030329: early spectrum
  52. IPN triangulation of GRB030414 (small error box)
  53. IPN triangulation of GRB030413 (small error box)
  54. Superluminal motion in GRB 030329 (Correction)
  55. Superluminal motion in GRB 030329
  56. GRB030329, optical position
  57. IPN triangulation of GRB030406 (small error box)
  58. IPN triangulation of GRB050403 (small error box)
  59. GRB 030329: BVRI photometry at Asiago
  60. GRB 030329: VLT V-band photometry
  61. Kiso observation of the GRB030329 at April 6
  62. GRB 030329, color evolution
  63. GRB030328, UBVRcIc field photometry
  64. GRB 030329 Optical observations
  65. GRB030329: Kiso B and R band observations
  66. GRB030328: R upper limit after 6 hours by MASTER
  67. SDSS 0.5m PT observations of GRB030329 (correction)
  68. SDSS 0.5m PT observations of GRB030329
  69. GRB030329: final R-band light curve by MASTER
  70. GRB030329, optical observation
  71. GRB030329, new UBVRcIc field photometry
  72. GRB 030329, light curve and SN prediction
  73. GRB 030329, BRI photometry
  74. GRB030328: Full Observation, X-ray Fading and Spectrum Measured
  75. GRB030329: Optical observations at Teramo
  76. GRB 030329: Radio observations at GMRT
  77. Further AAVSO V,B,R observations of GRB030329
  78. GRB 030329: Additional Mt. Laguna Optical Observations
  79. GRB 030329: Observations with ANDICAM
  80. GRB030329: further optical photometry and evidence for a light curve discontinuity
  81. triangulation of GRB 030331 (single error box)
  82. GRB 030329: optical observations
  83. Photometry of GRB030329 - Constant OT Magnitude
  84. GRB030329 - OT brightens
  85. GRB 030329, optical photometry
  86. GRB 030324: Optical and NIR Observations
  87. GRB030329: R band light curve by MASTER
  88. GRB030329 - Light curve flattening
  89. GRB 030324, optical search
  90. GRB 030329, optical observations
  91. GRB030328: X-ray Fading and Spectrum Measured with Chandra
  92. GRB030329a: detection by Konus-Wind
  93. GRB030329b: detection by Konus-Wind and Helicon-CoronasF
  94. GRB030329, BVRcIc field photometry
  95. GRB030329, SPM optical observations
  96. GRB 030329: Optical decay and synthesis
  97. GRB030329 optical observations
  98. GRB 030329: Optical pre-Imaging
  99. GRB 030329: Upper limit from 5.6 hours before trigger
  100. GRB030328: X-ray Afterglow Observed with Chandra

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