Photo of the Month
Check out the awesome new WALSWORTH GROUP sign on the door to the CfA lab!
(Incidentally, danger: we work with a lot of lasers and a pretty strong magnet :) )
Tests of the automated solar telescope are underway at the TNG / HARPS-N. We are using the solar telescope coupled to the HARPS-N spectrograph to look for the changes in the motion of the sun caused by Venus (Doppler spectroscopy) to demonstrate the capabilities of the HARPS-N spectrograph when calibrated with our astro-comb to detect earth-like exoplanets. We expect to operate this solar telescope for several hours every day for two years, after its enclosure and software have been completed, to study the motion of the sun over the course of several Venusian years.
The telescope, pointed directly at the sun, consists of a 3" achromatic lens focusing light into an integrating sphere (visible in the center foreground of the image) and is mounted on an amateur telescope mount. A guide camera with a 30 degree field of view (on top of telescope) is used to ensure that the telescope remains pointed at the sun. Light from the integrating sphere is then fed by optical fiber into the HARPS-N spectrograph. To allow the telescope to operate automatically, it will be housed inside an acrylic dome visible in the top of the image.
A slimy addition to the lab, Myxicola Infundibulum, is being housed for use of its giant axon in magnetic detection/imaging of neural activity using NV centers. Bottom: Matthew and John finding out why these
worms are called the slime fan worm.
A warm welcome to our new grad students: Tim Milbourne (left), Emma Rosenfeld (center), and
Matthew Turner (right). We're all looking forward to working with you!
We welcome the newest member to the Walsworth Group, the Nespresso Inissia, pictured on the
left, next to its predecessor. May you have many long, espresso-providing years with us!
We recently built a tube furnace for diamond annealing. One common method for synthesizing NV centers,
particularly in a thin layer close to the diamond surface as desired for many magnetic imaging applications, is to perform ion implantation to introduce nitrogen and vacancies into the diamond lattice. Subsequent annealing at
or above 800C mobilizes the vacancies, allowing them to diffuse to nearby substitutional nitrogen defects and
form NV centers. Here is Matthew and the furnace on its first test run.
We built a new enclosure for the "frankenfocal" setup to better isolate it from temperature variations and air currents in the optics room. Here Chinmay, Linh and David Glenn are carefully positioning the frame of the new enclosure around the confocal setup. For more pictures of this process as well as other recent lab activities, see the Photo Gallery page.
David Phillips shows off the operational astro-comb---integrated with the HARPS-N spectrograph and located
at the TNG telescope in the Canary Islands---to visiting astronomy dignitaries. Left-to-right in this photo:
Emilio Molinari, TNG Director; Tim de Zeeuw, Director General of the European Southern Observatory (ESO);
Rafael Rebolo,Director of the Instituto de Astrofísica de Canarias (IAC); and David Phillips.
During the recent Harvard Physics Graduate Alumni Reunion, we had a visit from former Walsworth group
graduate students Glenn Wong (far right, 2001 PhD) and David Bear (2nd from right, 2000 PhD). David and Glenn
are both prospering and look largely unchanged from grad school. Here they are posing with David Phillips and
Ron in the PG07 lab. Their PhD theses can be viewed on the Student Theses page.
Chinmay and Francesco building another NV confocal setup on the wooden optics table in the CfA lab--–mostly
out of spare equipment lying around from other setups, earning it the affectionate nickname frankenfocal.
(A) Optical image and (B) diamond magnetic image of magnetic sources in the Allende
chondrite meteorite. In collaboration with the group of Ben Weiss at MIT, we are
applying our wide-field, high-resolution diamond magnetic imager to map the remnant
magnetization in primitive meteorites, with the goal of directly constraining the magnetic
field strength that existed in the habitable zone of the solar system’s accreting nebula.