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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').
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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.

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

24378 results found.

  1. Magellan Observations of GRB030725 (=H2779)
  2. GRB030913 (=H2849): A GRB Possibly Localized by HETE
  3. XRF 020427: Gemini-South Spectroscopic Observations of the Host
  4. IBAS detection of bursts from SGR 1806-20
  5. IPN triangulation of GRB030830 (large error box)
  6. GRB 030824: Candidate Follow-Up
  7. XRF030824: Second-epoch Palomar observations
  8. GRB030823: optical observations
  9. GRB030823: Palomar observations
  10. XRF030824: Palomar observations
  11. GRB030823: optical observation at Tokyo Tech
  12. GRB 030821(=H2814): A Faint, Long GRB Localized by the HETE WXM and the IPN
  13. Summary of recent IPN and HETE detections of SGR bursts
  14. IPN detection of continued activity from SGR1806-20
  15. SGR 1808-20 (=H2802): A Possible new SGR
  16. IPN/HETE summary of recent bursts from SGR1806-20
  17. IBAS GRB Alerts 1011-1017 NOT CONFIRMED
  18. XRF030723: Re-analysis of ROTSE-III early images
  19. XRF030723 (=H2777): Second Epoch Magellan Observations
  20. GRB030725, possible optical transient
  21. XRF030723: Palomar observations and proposed counterpart
  22. GRB030725 (=H2779): A Bright GRB Localized by HETE
  23. XRF030723, BVRcIc field photometry correction
  24. XRF030723, ROTSE-III Early Observations
  25. XRF030723 (=H2777): An X-ray Flash Localized by the HETE WXM and
  26. Konus-Wind detection of the bursts from SGR1806-20 region
  27. IBAS GRB Alerts 969 970
  28. SGR 1806-20, submm observations
  29. H2768, H2770, and H2771: Three Bursts from SGR1806-20
  30. IPN triangulation of GRB030717 (annulus)
  31. 030716 NOT a GRB
  32. 030629 NOT a real GRB
  33. GRB030329: second XMM-Newton observation
  34. GRB030418: R optical observations
  35. GRB 030528: tentative NIR counterpart
  36. GRB030329, further radio observations at GMRT
  37. MASTER: optical observation GRB030601
  38. GRB030528(=H2724): Revised SXC Localization
  39. GRB 030329/SN 2003dh: Jitter Episode
  40. GRB 030528, Teramo optical observation
  41. GRB030528 (H2724): A long GRB localized by HETE
  42. GRB 030329: Correction to GCN 2254
  43. GRB 030329: Optical Observations
  44. GRB 030416: Optical Observations
  45. GRB030329, Optical observations
  46. GRB 030329/SN 2003dh: Possible increase in brightness
  47. GRB 021004: HST observations
  48. GRB030519B (=H2716): Peak Fluxes, Fluences, and Energy Spectrum
  49. GRB030519B (=H2716): A Long, Bright GRB Localized by the HETE WXM
  50. GRB 030329: Optical limit (contemporaneous imaging)
  51. GRB030329, BVRI photometry
  52. GRB 030329: Optical limit (contemporaneous photography)
  53. GRB030429 (=H2695): A Long GRB Localized by the HETE WXM and SXC
  54. GRB030418 (=H2686): A Long, X-Ray-Rich GRB Localized by the HETE WXM
  55. XRF030416 (=U10897): An X-Ray Flash Localized by the HETE WXM
  56. GRB 030329: all-sky CCD images by K. Shiokawa immediately after the burst
  57. GRB030501, optical observation
  58. GRB030501 triangulation (correction to GCN 2194)
  59. GRB 030329 Optical Observations
  60. GRB030328, optical observation
  61. GRB 030329, BVRI photometry
  62. IPN triangulation of GRB030501 (IBIS event; annulus)
  63. GRB030501 localized by INTEGRAL
  64. IPN triangulation of GRB030428 (two large error boxes)
  65. GRB 030429: ROTSE-III observations
  66. GRB030329 observed as a sudden ionospheric disturbance (SID)
  67. IPN triangulation of GRB030426 (annulus)
  68. GRB 030329: optical spectropolarimetry at VLT
  69. GRB030329, optical observation
  70. MASTER:optical observations GRB030416
  71. ROTSE-III prompt optical detections of GRB 030418
  72. GRB 030418: Optical afterglow candidate
  73. GRB030329: Optical Observations
  74. GRB030329, UBVRI polarimetry, R-polarization
  75. GRB 030329: SARA Optical Observations
  76. OT GRB 030329: early spectrum
  77. GRB030324: Candidate Optical Afterglow
  78. Superluminal motion in GRB 030329 (Correction)
  79. Superluminal motion in GRB 030329
  80. GRB 030329 and SN 2003dh
  81. GRB 030329 VLBA Observations
  82. GRB030328, UBVRcIc field photometry
  83. GRB 030329: possible color change
  84. GRB030329: RTT150 optical observations
  85. GRB030329: Kiso B and R band observations
  86. GRB030329: More AAVSO VR obs
  87. GRB 030329: SARA Optical Observations
  88. GRB 030329: SARA Optical Observations
  89. GRB030329: Optical observations
  90. GRB030329, cessation of fading
  91. GRB 030329: SARA Optical Observations
  92. GRB030329, optical observation
  93. GRB030329, optical observation
  94. GRB030329, new UBVRcIc field photometry
  95. GRB 030329, light curve and SN prediction
  96. GRB030328: Full Observation, X-ray Fading and Spectrum Measured
  97. GRB030329: Optical observations at Teramo
  98. GRB 030329: Radio observations at GMRT
  99. Further AAVSO V,B,R observations of GRB030329
  100. GRB 030329: Observations with ANDICAM

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