|
MY RESEARCH
(Click to select descriptive pages) |
|
I am an observational astronomer with interests in stellar
evolution. My students and I work primarily with photometry
and spectroscopy in the optical region of the spectrum. You
can link to some of the places I work at below---notably the
Gettysburg College Observatory and the National Undergraduate
Research Observatory (NURO)----and there are links to PDF versions
of selected papers at the end of this page
Areas of Research Include:
- High precision measurements of eclipsing/spectroscopic
binary systems.
- Properties of open clusters.
- Rotation and activity in young stars.
- Light curves of supernovas.
- Asteroid astrometry and photometry.
I have also published papers on
- Radial velocity curves of cepheids.
- Shadow bands at solar eclipses.
- Nuclear abundances in interstellar clouds using high
resolution spectroscopy (my Ph.D. thesis).
- Physics and astronomy education. (see also Project CLEA
pages)
|
|
Observatories |
Gettysburg College Observatory
Our main research instrument is a 16 inch (0.4m) f/11
Cassegrain equipped with a back-illuminated 1k square CCD camera
(SiTE 003B chip, Roper Scientific camera), thermoelectrically
cooled.
|
 |
National Undergraduate Research Observatory (NURO)
The telescope, owned by Lowell Observatory in Flagstaff, AZ,
is a 32in (0.8 m) f/15 Cassegrain with a 2K back-illuminated CCD
chip, LN cooled.
|
 |
|
A Selection of Papers (PDF
format)
* indicates student co-author |
|
Binary Stars |
-
Torres, Guillermo, Lacy, Claud H.
Sandberg, Marschall, Laurence A., and Sheets, Holly A.*, “The
Eclipsing Binary V1061 Cygni: Confronting Stellar Evolution
Models for Active and Inactive Solar-Type Stars”, Astrophys..
Journal, 640, 1018-1038 (2006)
-
Mader, Jeff A., Torres, Guillermo,
Marschall, Laurence A., and Rizvi, Akbar H.*, “Optical
Photometry and Spectroscopy of the ‘Cool Algol’ AV Delphinus:
Determination of the Physical Properties”, Astron. Journal,
130, 234 (2005)
-
Torres, Guillermo, Mader, Jeff A.,
Marschall, Laurence A., Neuhäuser, Ralph, and Duffy*, Alaine S.,
“Optical Photometry and X-Ray Monitoring of the “Cool Algol”
BD+05˚706: Determination of the Physical Properties”, Astron.
Journal, 125, 3237 (2003)
-
Marschall, L.A., Stefanik, R.P., Lacy, C.H., Torres, G.,
Williams, D.B., and Agerer, F., "The Eclipsing Double-lined
Spectroscopic Binary System V505 Persei", Astron. Journal,
114, 793 (1997)
-
Marschall, L.A., and Mathieu, Robert D. "Parenago 1540: A
Premain-Sequence Double-Lined Spectroscopic Binary Near the
Orion Trapezium," Astron. Journal, 96, 1956
(1988)
|
|
Supernovas |
-
Jha, S., Garnavich, P.M., Kirshner, R.P., Challis, P.M.,
Soderberg, A.M., Macri, L.M., Huchra, J. P., Barmby, P.,
Barton, E.J., Berlind, P., Brown, W., Caldwell, N., Calkins,
M.L., Kannappan, S.J., Koranyi, D.M., Pahre, M.A., Rines,
K.J., Stanek, K.Z., Stefanik, R.P., Szentgyorgi, A.H.,
Vaisanen, P., Wang, Z., Zajac, J, Riess, A.G., Filippenko,
A.V., Li, W., Modjaz, M., Treffers, R.R., Hergenrother, C.W.,
Grebel, E.K., Seitzer, P., Jacoby, G.H., Benson, P.J.,
Rizvi, A.*, Marschall, L.A., Goldader, J., Beasley, M.,
Vacca, W.D., Leibundgut, B., Spyromilio, J., Schmidt, B.,
and Wood, P.R., "The Type-Ia Supernova 1998bu in M96 and
the Hubble Constant", Astrophysical Journal Suppl.,
125, 73-97 (1999)
-
Richmond, M.R., Treffers, R.R., Filippenko, A.V., Van Dyk,
S., Paik, Young, Marschall, L.A., Laaksonen, B.D.*,
Macintosh, B., and McLean, I.S., "UBVRI Photometry of
SN1994D in NGC 4526", Astron. Journal, 109,
2121 (1995)
|
|
Open Clusters |
-
Montgomery, K.A, Marschall, L.A., and Janes, K.A., "CCD
Photometry of the Old Open Cluster, M67", Astron. J.,
106, 181 (1993).
-
Marschall, L.A., and Van Altena, William F. "Membership
in the Young Cluster Trumpler 37", Astron. Journal,
94, 71 (1987).
|
|
Asteroids |
-
Ratcliff, Stephen J., Balonek, Thomas J., Marschall,
Laurence A., DuPuy, David L., Pennypacker, Carlton R, Verma,
Ritu*, Alexov, Anastasia*, and Bonney, Vivian*, "The
Measurement of Astronomical Parallaxes with CCD Imaging
Cameras on Small Telescopes", American Journal of Physics,
61, 208 (1993).
|
|
Miscellaneous: Cepheids, Interstellar Lines, etc. |
-
Marschall, L.A., Seeds, M.A., and Davis, R.J., "Radial
Velocity and Light Variations of IR Cephei", Astron.
Journal, 106, 1123 (1993).
-
Marschall, L.A., and Hobbs, L.M., "Interferometric Studies
of Interstellar Calcium Lines", Astrophys. Journal,
177, 43-62 (1972).
|
|
Project CLEA and other Educational Articles |
-
Marschall, Laurence A.,
Snyder, Glenn A., and Cooper, P.Richard, "A Desktop Universe for
the Introductory Astronomy Laboratory", The Physics Teacher,
38, 536, (2000)
|