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Yale Astronomy

N2K: a search for hot jupiters

Project Overview

Ongoing precise radial velocity surveys of ~2000 stars have discovered hundreds of extrasolar planets, including several "Hot Jupiters": massive planets orbiting surprisingly close to their host stars. Fortuitous alignment of the orbital planes has caused several such planets to transit in front of bright host stars, revealing a wealth of information about these planets: density, composition, and even interior structure.

The N2K Consortium is a multinational, distributed observing program searching the "Next 2000" stars not already being surveyed. Its goal is to discover dozens of new hot jupiters, and learn more about their internal and atmospheric properties.

Hot Jupiter
Artwork by Greg Laughlin


Using the now well-established correlation between host stars' heavy element abundance and the frequency of planets, we select high metallicity stars from a pool of 14,000. Planets then found in small orbits (P < 14 days) have relatively high probability for transit (~10%) and are monitored photometrically at Fairborn Observatory. A full description of our technique can be found in the Fischer et al. 2004 paper, below.


Publications from the N2K consortium. The number in parentheses after each publication shows the cummulative total number of planets discovered to date through N2K:

  1. Giguere, M. J., Fischer, D. A., Payne, M. J., Brewer, J. M., Johnson, J. A., Howard, A. W., Isaacson, Howard T. 2015, "Newly Discovered Planets Orbiting HD 5319, HD 11506, HD 75784 and HD 10442 from the N2K Consortium" ApJ, 799, 89 (34)
  2. Giguere, M. J., Fischer, D. A., Howard, A. W., Johnson, J. A., Henry, G. W., Wright, J. T., Marcy, G. W., Isaacson, H. T., Hou, F., Spronck, J. F. P., 2012 "A High-eccentricity Component in the Double-planet System around HD 163607 and a Planet around HD 164509" ApJ, 744, 1 (30)
  3. Harakawa, H, Sato, B,m Fischer, D. A., Ida, S., Omiya, M., Johnson, J. A., Marcy, G. W., Toyota, E., Hori, Y., Howard, A. W., 2010 "Detection of a Low-eccentricity and Super-massive Planet to the Subgiant HD 38801" ApJ, 715, 550 (27)
  4. Sato, B., Fischer, D.A., Ida, S. Harakawa, H, Omiay, M., Johnson, J. A., Marcy, G.W., Toyota, E., Hori, Y., Isaacson, H., Howard, A.W., Peek, K.M.G., 2009 "A Substellar Companion in a 1.3 yr Nearly Circular Orbit of HD 16760" ApJ, 703, 671 (26)
  5. Valenti, J. A., Fischer,D., Marcy, G. W., Johnson, J. A., Henry, G. W., Wright, J. T., Howard, A. W., Giguere, M., Isaacson, H., 2009 "Two Exoplanets Discovered at Keck Observatory" ApJ 702, 989 (25)
  6. Wright, J. T., Fischer, D. A., Ford, E. B., Veras, D., Wang, J., Henry, G. W., Marcy, G. W., Howard, A. W., Johnson, J. A., 2009 "A Third Giant Planet Orbiting HIP 14810" ApJ 699L, 97 (23)
  7. Wright, J. T., Upadhyay, S., Marcy, G. W., Fischer, D. A., Ford, E. B., Johnson, J. A., 2009 "Ten New and Updated Multi-planet Systems, and a Survey of Exoplanetary Systems" ApJ, 693, 1084 (22)
  8. Peek, K. M. G., Johnson, J. A., Fischer, D. A., Marcy, G. W., Henry, G.W. Howard, A.W., Wright, J.T., Lowe, T.B., Reffert, S., Schwab, C., Williams, P. K. G. , Isaacson, H. Giguere, M. J., 2009 "Old, Rich, and Eccentric: Two Jovian Planets Orbiting Evolved Metal-Rich Stars" PASP, 121, 613 (20)
  9. López-Morales, Mercedes; Butler, R. Paul; Fischer, Debra A.; Minniti, Dante; Shectman, Stephen A.; Takeda, Genya; Adams, Fred C.; Wright, Jason T.; Arriagada, Pamela, 2008 "Two Jupiter-Mass Planets Orbiting HD 154672 and HD 205739" AJ 136 (18)
  10. Fischer, D.A., 2008 "Mapping the Realm of Hot Jupiters" PhST, 130a4002.
  11. Robinson, Sarah E.; Laughlin, Gregory; Vogt, Steven S.; Fischer, Debra A.; Butler, R. Paul; Marcy, Geoffrey W.; Henry, Gregory W.; Driscoll, Peter; Takeda, Genya; Johnson, John A., 2007 "Two Jovian-Mass Planets in Earthlike Orbits" ApJ 670 (16)
  12. Wright, J. T.; Marcy, G. W.; Fischer, D. A.; Butler, R. P.; Vogt, S. S.; Tinney, C. G.; Jones, H. R. A.; Carter, B. D.; Johnson, J. A.; McCarthy, C.; Apps, K., 2007 "Four New Exoplanets and Hints of Additional Substellar Companions to Exoplanet Host Stars" ApJ 657 (14)
  13. Fischer, D. A., Vogt, S. S., Marcy, G. W., Butler, R. P., Sato, B., Henry, G. W., Robinson, S., Laughlin, G., Ida, S., Toyota, E., Omiya, M., Driscoll, P., Takeda, G., Wright, J. T., Johnson, J. A., 2007 "Five Intermediate-Period Planets from the N2K Sample" ApJ, 669 (12)
  14. Robinson, Sarah E.; Ammons, S. Mark; Kretke, Katherine A.; Strader, Jay; Wertheimer, Jeremy G.; Fischer, Debra A.; Laughlin, Gregory., 2007 "The N2K Consortium. VII. Atmospheric Parameters of 1907 Metal-rich Stars: Finding Planet-Search Targets" ApJS 169, 430
  15. Johnson, J., A., Marcy, G. W., Fischer, D. A., Laughlin, G., Butler, R. P., Henry, G. W., Valenti, J. A., Ford, E. B., Vogt, S. S., Wright, J. T., 2006 "The N2K Consortium VI: Doppler Shifts Without Templates and Three New Short-Period Planets." ApJ, 647 (7)
  16. Bozorgnia, N., Fortney, J., McCarthy, C., Fischer, D. A., Marcy, G., 2006 "Search for an Atmospheric Signature in the Transiting Planet HD149026" PASP, 118, 1252
  17. Robinson, S. E., Strader, J., Ammons, S. M., Laughlin, G., Fischer, D. A., 2006 "The N2K Consortium. V. Identifying Very Metal-rich Stars with Low- Resolution Spectra: Finding Planet-Search Targets" ApJ 637, 1102
  18. Ammons, S.M., Robinson, S. E., Strader, J., Laughlin, G., Fischer, D., Wolf, A., 2006 "The N2K Consortium. IV. New Temperatures and Metallicities for More than 100,000 FGK Dwarfs" ApJ, 638, 1004
  19. Fischer, D. et al., 2006 "The N2K Consortium. III. Short-Period Planets Orbiting HD 149143 and HD 109749" ApJ 637, 1094 (4)
  20. Sato, et al, 2005 "The N2K Consortium. II. A Transiting Hot Saturn Around HD 149026 with a Large Dense Core" ApJ 633, 465 (2) Over 200 citations.
  21. Fischer, D., et al, 2004 "The N2K Consortium. I. A Hot Saturn Planet Orbiting HD 88133" ApJ 620, 481 (1) 66 citations.