You have stumbled onto Jay Farihi's homepage...

 

 

 

Incriminating information:

 

I have recently started a faculty position at University College London after a brief and productive year at the Institute of Astronomy in Cambridge.  I am a 2012 Ernest Rutherford Fellow.

 

My main research activity is digging up evidence of terrestrial planetary systems at stellar corpses known as white dwarfs.  One might not expect to find the surviving planetary systems around dead stars, but the universe is full of surprises.  In fact, it is likely we will learn more about extrasolar terrestrial planets using white dwarfs than via any other method.  This is because cool white dwarfs have pure hydrogen and helium atmospheres, and those stars with rocky planetary systems can become polluted by small yet detectable amounts of heavy elements, such as metals.  We can use this metal pollution to measure the composition of the rocky planetary material, and even identify water.

 

I continue to use the Spitzer Space Telescope to analyze the rocky debris around white dwarfs; the current picture is that they externally polluted with heavy elements from tidally destroyed asteroids.  The compositions we have measured so far are similar to the material found in the inner Solar System (i.e. like Earth!).  Currently, we estimate at least a few percent, and as many as 20-30% of all white dwarfs harbor terrestrial planetary system remnants.  Relevant publications and press releases can be found below.

 

I left Gemini Observatory on the big island of Hawaii in mid-2007, where among other things, I trained for and finished my first Marathon; a huge thanks to all my friends and family for their support. 

 

 

 

Fond memories:

 

As a graduate student, I worked with Eric Becklin & Ben Zuckerman searching for low mass stellar and substellar companions to nearby white dwarfs. The bulk of my thesis is published in an ApJ Supplement Series paper.  If you want all the gory details (they are both plentiful and colorful), you can find my thesis here:

 

http://whitedwarf.org/theses/farihi.pdf

 

The central result of my thesis: a spectral type histogram of low mass companions to white dwarfs.  The drop off in companion frequency is clearly above the minimum mass for hydrogen burning, which corresponds to an early L dwarf spectral type / temperature at typical white dwarf ages of one to a few Gyr.  Our sensitivity is off the chart.  As with solar-type main sequence stars, intermediate mass stars (the progenitors of white dwarfs) with brown dwarf companions are rare. 

 

 

 

Passions, obsessions, lust for knowledge:

 

The ultimate fate of planetary systems

 

Origin and evolution of low mass objects

 

The local cool white dwarf population

 

Digging in the stellar graveyard

 

 

I have been very fortunate to have several of my own space-based research programs on the Hubble + Spitzer Space Telescopes.  Many are posted below with more on the way...

 

 

 

Opinions backed by evidence:

 

45) Evidence for Water in the Rocky Debris of a Disrupted Extrasolar Minor Planet: astro-ph | Science | press | BBC | Hubble | Nature

 

44) Evidence of Rocky Planetesimals Orbiting Two Hyades Stars: astro-ph | MNRAS | press | BBC

 

43) Orbital and Evolutionary Constraints on the Planet Hosting Binary GJ 86 from the Hubble Space Telescope: astro-ph | MNRAS

 

42) The WIRED Survey III: An Infrared Excess around the Eclipsing Post-Common Envelope Binary SDSS J030308.35+005443.7: astro-ph | ApJ

 

41) Precision Astrometry of the Exoplanet Host Candidate GD 66: astro-ph | MNRAS

 

40) The Chemical Diversity of Exoterrestrial Planetary Debris Around White Dwarfs: astro-ph | MNRAS | press

 

39) Scars of Intense Accretion Episodes at Metal-Rich White Dwarfs: astro-ph | MNRAS

 

38) Gaseous Material Orbiting the Polluted White Dwarf HE 1349-2305: astro-ph | ApJ

 

37) The Origin of Circumstellar Features in the Spectra of Hot DA White Dwarfs: astro-ph | MNRAS

 

36) Constraints on the Lifetimes of Disks Resulting from Tidally Destroyed Rocky Planetary Bodies: astro-ph | ApJ

 

35) A Trio of Metal-Rich Dust and Gas Disks Found Orbiting Candidate White Dwarfs with K-Band Excess: astro-ph | MNRAS

 

34) An Extremely Luminous Panchromatic Outburst from the Nucleus of a Distant Galaxy: astro-ph | Science | BBC

 

33) Evolutionary Constraints on the Planet-Hosting Subgiant epsilon Reticulum from its White Dwarf Companion: astro-ph | MNRAS

 

32) Accretion of a Terrestrial-Like Minor Planet by a White Dwarf: astro-ph | ApJ

 

31) The Magnetic and Metallic Degenerate G77-50: astro-ph | MNRAS

 

30) Possible Signs of Water and Differentiation in a Rocky Exoplanetary Body: astro-ph | ApJL

 

29) White Dwarf - Red Dwarf Systems Resolved with the Hubble Space Telescope. II. Full Snapshot Survey Results: astro-ph | ApJS

 

28) A Detailed Model Atmosphere Analysis of Cool White Dwarfs in the Sloan Digital Sky Survey: astro-ph | ApJS

 

27) Strengthening the Case for Asteroidal Accretion: Evidence for Subtle and Diverse Disks at White Dwarfs: astro-ph | ApJ

 

26) Does GD 356 Have a Terrestrial Planetary Companion?: astro-ph | MNRAS

 

25) Rocky Planetesimals as the Origin of Metals in DZ Stars: astro-ph | MNRAS | press

 

24) IRTF Observations of White Dwarfs with Possible Near-Infrared Excess: astro-ph | MNRAS

 

23) Deep Imaging Survey of Young, Nearby Austral Stars. VLT / NACO Near-infrared Lyot-Coronographic Observations: astro-ph | A&A

 

22) A Glimpse of the End of the Dark Ages: The Gamma-Ray Burst of 23 April 2009 at Redshift 8.3: astro-ph | Nature | BBC

 

21) X-Ray and Infrared Observations of Two Externally-Polluted White Dwarfs: astro-ph | ApJ | press

 

20) PHL 5038: A Spatially Resolved White Dwarf - Brown Dwarf Binary: astro-ph | A&A

 

19) Infrared Signatures of Disrupted Minor Planets at White Dwarfs: astro-ph | ApJ | press | BBC

 

18) Six White Dwarfs with Circumstellar Silicates: astro-ph | AJ | press

 

17) Spitzer IRAC Observations of White Dwarfs. II. Massive Planetary and Cold Brown Dwarf Companions to Young and Old Degenerates: astro-ph | ApJ

 

16) Near-Infrared Constraints on the Presence of Warm Dust at Metal-Rich Helium Atmosphere White Dwarfs: astro-ph | AJ

 

15) Spitzer IRAC Observations of White Dwarfs. I. Warm Dust at Metal-Rich Degenerates: astro-ph | ApJ

 

14) A Near-Infrared Spectroscopic Study of the Accreting Magnetic White Dwarf SDSS J121209.31+013627.7 and Its Substellar Companion: astro-ph | ApJ | press

 

13) Externally Polluted White Dwarfs with Dust Disks: astro-ph | ApJ

 

12) Infrared Emission from the Dusty Disk Orbiting GD 362, an Externally Polluted White Dwarf: astro-ph | AJ | press

 

11) The Nature of the Close Magnetic White Dwarf - Probable Brown Dwarf Binary SDSSJ121209.31+013627.7: astro-ph | MNRAS

 

10) HST NICMOS Imaging of the Planetary-mass Companion to the Young Brown Dwarf 2MASSW J1207334-393254: astro-ph | ApJ | press

 

9) White Dwarf - Red Dwarf Systems Resolved with the Hubble Space Telescope. I. First Results: astro-ph | ApJ

 

8) Low-Luminosity Companions to White Dwarfs (thesis work): astro-ph | ApJS                                                         

 

7) Mid-Infrared Observations of the White Dwarf - Brown Dwarf Binary GD 1400: astro-ph | AJ

 

6) A Dusty Disk around GD 362, a White Dwarf with a Uniquely High Photospheric Metal Abundance: astro-ph | ApJL | press

 

5) SSSPM J1549-3544 Is Not a White Dwarf: astro-ph | ApJL

 

4) Cool versus Ultracool White Dwarfs: astro-ph | AJ

 

3) A Possible Brown Dwarf Companion to the White Dwarf GD 1400: astro-ph | AJ

 

2) Discovery of an Ultracool White Dwarf Companion: astro-ph | ApJ

 

1) Mid-Infrared Observations of van Maanen 2: No Substellar Companion: astro-ph | ApJL

 

 

 

Meme exchange:

 

Jay Farihi

 

Ernest Rutherford Fellow

 

Physics and Astronomy

 

University College London

 

London WC1E 6BT

 

United Kingdom

 

 

Phone: +44 207 679 7991

 

 

jfarihi at star.ucl.ac.uk