Astrophysics Research

From 2007-2012 I was a Hubble Fellow and Menzel Fellow at the Harvard-Smithsonian Center for Astrophysics. I got my PhD in astronomy at UC-Santa Cruz/Lick Observatory. I am a proud member of the SAGES group, which studies extragalactic globular cluster systems as a means to understand galaxy formation. Our current focus is the SLUGGS survey. I have broad interests in old stellar populations, including star clusters in the local universe and mass loss in red giants. I also study black holes in globular clusters.

I can be reached at: NOstraderSPAM@pa.msu.edu

Refereed papers:

• The SLUGGS survey: Probing the supermassive black hole connection with bulges and haloes using red and blue globular cluster systems.
  Pota, V., Graham, A., Forbes, D., Romanowsky, A., Brodie, J., Strader, J.

• The SLUGGS survey: Kinematics for over 2500 globular clusters in twelve early-type galaxies.
  Pota, V., Forbes, D., Romanowsky, A., Brodie, J., Spitler, L., Strader, J., Foster, C., Arnold, J., Benson, A., Blom, C., Hargis, J., Rhode, K., Usher, C. 2013, MNRAS, 428, 389
• Deep Chandra monitoring observations of NGC 4649: I. Catalog of source properties.
  Luo, B., Fabbiano, G., Strader, J., Kim, D.-W., Brodie, J., Fragos, T., Gallagher, J., King, A., Zezas, A. 2013, ApJS, 204, 14
• Two stellar-mass black holes in the globular cluster M22.
  Strader, J., Chomiuk, L., Maccarone, T., Miller-Jones, J., Seth, A. 2012, Nature, 490, 71
• The 10830 He I absorption line among metal-poor subdwarfs.
  Smith, G., Dupree, A., Strader, J. 2012, PASP, 124, 1252
• Deep Chandra monitoring observations of NGC 4649: II. Wide-field Hubble Space Telescope imaging of the globular clusters.
  Strader, J., Fabbiano, G., Luo, B., Kim, D.-W., Brodie, J., Fragos, T., Gallagher, J., Kalogera, V., King, A., Zezas, A. 2012, ApJ, 760, 87. (Table 1 from paper)

• The SLUGGS survey: NGC 3115, a critical test case for metallicity bimodality in globular cluster systems.
  Brodie, J., Usher, C., Conroy, C., Strader, J., Arnold, J., Forbes, D., Romanowsky, A. 2012, ApJL, 759, 33
• A variable ultraluminous X-ray source in a globular cluster in NGC 4649.
  Roberts, T., Fabbiano, G., Luo, B., Kim, D.-W., Strader, J., Middleton, M., Brodie, J., Fragos, T., Gallagher, J., Kalogera, V., King, A., Zezas, A. 2012, ApJ, 760, 135
• Detailed abundance analysis from integrated high-dispersion spectroscopy: Globular clusters in the Fornax dwarf spheroidal.
  Larsen, S., Brodie, J., Strader, J. 2012, A&A, 546, A53
• Radially extended kinematics of the S0 galaxy NGC 2768 from planetary nebulae, globular clusters and starlight.
  Forbes, D., Cortesi, A., Pota, V., Foster, C., Romanowsky, A., Merrifield, M., Brodie, J., Strader, J., Coccato, L., Napolitano, N. 2012, MNRAS, 426, 975
• The SLUGGS Survey: Calcium triplet-based spectroscopic metallicities for over 900 globular clusters.
  Usher, C., Forbes, D., Brodie, J., Foster, C., Spitler, L., Arnold, J., Romanowsky, A., Strader, J., Poza, V. 2012, MNRAS, 426, 1475

• The SLUGGS Survey: Globular cluster system kinematics and substructure in NGC 4365.
  Blom, C., Forbes, D., Brodie, J., Foster, C., Romanowsky, A., Spitler, L., Strader, J. 2012, MNRAS, 426, 1959
• Constraints on mass loss and self-enrichment scenarios for the globular clusters of the Fornax dSph.
  Larsen, S., Strader, J., Brodie, J. 2012, A&A, 544, 14
• Tidal signatures in the faintest Milky Way satellites: The detailed properties of Leo V, Pisces II and Canes Venatici II.
  Sand, D., Strader, J., Willman, B., Zaritsky, D., McLeod, B., Caldwell, N., Seth, A., Olszewski, E. 2012, ApJ, 756, 79
• "Galaxy," defined.
  Willman, B., Strader, J. 2012, AJ, 144, 76
• Evidence for inhomogeneous reionization in the local universe from metal-poor globular cluster systems.
  Spiter, L., Romanowsky, A., Diemand, J., Strader, J. Forbes, D., Moore, B., Brodie, J. 2012, MNRAS, 423, 2177

• No evidence for intermediate-mass black holes in globular clusters: Strong constraints from the JVLA.
  Strader, J., Chomiuk, L., Maccarone, T., Miller-Jones., J., Seth, A., Heinke, C., Sivakoff, G. 2012, ApJL, 2012, 750, 27
• An optical/NIR survey of globular clusters in early-type galaxies. III. On the color bimodality of GC systems.
  Chies-Santos, A., Larsen, S., Cantiello, M., Strader, J., Kuntschner, H., Wehner, E., Brodie, J. 2012, A&A, 539, 54
• The ongoing assembly of a central cluster galaxy: Phase-space substructures in the halo of M87.
  Romanowsky, A., Strader, J., Brodie, J., Mihos, C., Spitler, L., Forbes, D., Foster, C. 2012, ApJ, 748, 29
• Old massive globular clusters and the stellar halo of the dwarf starburst galaxy NGC 4449.
  Strader, J., Seth, A., Caldwell, N. 2012, AJ, 143, 52
• Wide-field precision kinematics of the M87 globular cluster system.
  Strader, J., Romanowsky, A., Brodie, J., Spitler, L., Beasley, M., Arnold, J., Tamura, N., Sharples, R., Arimoto, N. 2011, ApJS, 197, 33

• The relationships among compact stellar systems: A fresh view of ultra compact dwarfs.
  Brodie, J., Romanowsky, A., Strader, J., Forbes, D., 2011, AJ, 142, 199
• Hubble Space Telescope photometry of globular clusters in M81.
  Nantais, J., Huchra, J., Zezas, A., Gazeas, K., Strader, J., 2011, AJ, 142, 183
• Willman 1 — A probable dwarf galaxy with an irregular kinematic distribution.
  Willman, B., Geha, M., Strader, J., Strigari, L., Simon, J., Kirby, E., Ho, N., Warres, A. 2011, AJ, 142, 128
• Spectra of globular clusters in the Sombrero galaxy: Evidence for spectroscopic metallicity bimodality.
  Alves-Brito, A., Hau, G., Forbes, D., Spitler, L., Strader, J., Brodie, J., Rhode, K. 2011, MNRAS, 417, 1823
• The globular cluster population of NGC 7457: Clues to the evolution of field S0 galaxies.
  Hargis, J., Rhode, K., Strader, J., Brodie, J. 2011, ApJ, 738, 113

• The fossil record of two-phase galaxy assembly: Kinematics and metallicities in the nearest S0 galaxy.
  Arnold, J., Romanowsky, A., Brodie, J., Chomiuk, L., Spitler, L., Strader, J., Benson, A., Forbes, D. 2011, ApJL, 736, 26
• Global properties of "ordinary" early-type galaxies: Photometry and spectroscopy of stars and globular clusters in NGC 4494.
  Foster, C., Spitler, L., Romanowsky, A., Forbes, D., Pota, V., Bekki, K., Strader, J., Proctor, R., Arnold, J., Brodie, J. 2011, MNRAS, 415, 3393
• Star clusters in M31: V. Internal dynamical trends: Some troublesome, some reassuring.
  Strader, J., Caldwell, N., Seth, A. 2011, AJ, 142, 8
• Evidence for two phases of galaxy formation from radial trends in the globular cluster system of NGC 1407.
  Forbes, D., Spitler, L., Strader, J., Romanowsky, A., Brodie, J., Foster, C. 2011, MNRAS, 413, 2943
• Direct evidence for an enhancement of helium in giant stars in Omega Centauri.
  Dupree, A., Strader, J., Smith, G. 2011, ApJ, 728, 155

• An optical/NIR survey of globular clusters in early-type galaxies. II. Ages of GC systems and the relation to galaxy morphology.
  Chies-Santos, A., Larsen, S., Kuntschner, H., Anders, P., Wehner, E., Strader, J., Brodie, J., Santos Jr., J. 2011, A&A, 525, 20
• An optical/NIR survey of globular clusters in early-type galaxies. I. Introduction and data reduction procedures.
  Chies-Santos, A., Larsen, S., Wehner, E., Kuntschner, H., Strader, J., Brodie, J. 2011, A&A, 525, 19
• Deriving metallicities from the integrated spectra of extragalactic globular clusters using the near-infrared calcium triplet.
  Foster, C., Forbes, D., Proctor, R., Strader, J., Brodie, J., Spitler, L. 2010, AJ, 139, 1566
• Star cluster candidates in M81.
  Nantais, J., Huchra, J., McLeod, B., Strader, J., Brodie, J. 2010, AJ, 139, 1413
• A blue tilt in the globular cluster system of the Milky Way-like galaxy NGC 5170.
  Forbes D., Spitler, L., Harris, W., Bailin, J., Strader, J., Brodie, J., Larsen, S. 2010, MNRAS, 403, 429

• An HST/WFPC2 survey of bright young clusters in M31. IV. Ages and mass estimates.
  Perina, S., et al. 2010, A&A, 511, 23
• An HST/WFPC2 survey of bright young clusters in M31. III. Structural parameters.
  Barmby, P., Perina, S., Bellazzini, M., Cohen, J., Hodge, P., Huchra, J., Kissler-Patig, M., Puzia, T., Strader, J. 2009, AJ, 138, 1667
• Fast winds and mass loss from metal-poor field giants.
  Dupree, A., Smith, G., Strader, J.. 2009, AJ, 138, 1485
• A survey of UV bright sources behind the halo of M31.
  Fittinghoff, A., Prochaska, X., Kalirai, J., Strader, J., Guhathakurta, P., Kaplan, K. 2009, MNRAS, 399, 728
• An HST/WFPC2 survey of bright young clusters in M31. II. Photometry of less luminous clusters in the fields.
  Hodge, P., Krienke, O., Bellazzini, M., Perina, S., Barmby, P., Cohen, J., Puzia, T., Strader, J.. 2009, AJ, 138, 770

• Mass-to-light ratios for M31 globular clusters: Age-dating and a surprising metallicity trend.
  Strader, J., Smith, G., Larsen, S., Brodie, J., Huchra, J. 2009, AJ, 138, 547
• Probing the 2-D kinematic structure of early-type galaxies out to 3 effective radii.
  Proctor, R., Forbes, D., Romanowsky, A., Brodie, J., Strader, J., Spolaor, M., Mendel, T., Spitler, L. 2009, MNRAS, 398, 91
• Evidence for the disky origin of luminous Virgo dwarf ellipticals from the kinematics of their globular cluster systems.
  Beasley, M., Cenarro, J., Strader, J., Brodie, J. 2009, AJ, 137, 5146
• Mapping the dark side with DEIMOS: globular clusters, X-ray gas, and dark matter in the NGC 1407 group.
  Romanowsky, A., Strader, J., Spitler, L., Johnson, R., Brodie, J., Forbes, D., Ponman, T. 2009, AJ, 137, 4956
• An ultra compact dwarf around the Sombrero galaxy (M104): The nearest massive UCD.
  Hau, G., Spitler, L., Forbes, D., Proctor, R., Strader, J, Mendel, T., Brodie, J., Harris, W. 2009, MNRAS, 394, 97

• The least luminous galaxy: Spectroscopy of the Milky Way satellite Segue 1.
  Geha, M., Willman, B., Simon, J., Strigari, L., Kirby, E., Law, D., Strader, J. 2009, ApJ, 692, 1464
• An HST/WFPC2 survey of bright young clusters in M31. I. VdB0, a massive star cluster seen at t~25 Myr.
  Perina, S., et al. 2009, A&A, 494, 933
• The origin of the blue tilt in extragalactic globular cluster systems.
  Strader, J., Smith, G. 2008, AJ, 136, 1828
• A probable new globular cluster in the Galactic disk.
  Strader, J., Kobulnicky, H. 2008, AJ, 136, 2102
• A glimpse into the past: The recent evolution of globular clusters.
  Kalirai, J., Strader, J., Anderson, J., Richer, H. 2008, ApJL, 682, 37

• The peculiar globular cluster system of the S0 galaxy NGC 7457.
  Chomiuk, L., Strader, J., Brodie, J. 2008, AJ, 136, 234
• The connection between globular cluster systems and their host galaxy and environment: A case study of the isolated elliptical NGC 821.
  Spitler, L., Forbes, D., Strader, J., Brodie, J., Gallagher, J. 2008, MNRAS, 385, 361
• Keck spectroscopy of globular clusters in the spiral galaxy NGC 2683.
  Proctor, R., Forbes, D., Brodie, J., Strader, J. 2008, MNRAS, 385, 1709
• Carbon isotope ratios on the upper red giant branch of Messier 71.
  Smith, G., Shetrone, M., Strader, J. 2007, PASP, 119, 722
• Stellar populations of globular clusters in the elliptical galaxy NGC 1407.
  Cenarro, J., Beasley, M., Strader, J., Brodie, J., Forbes, D. 2007, AJ, 134, 391

• Spatially resolved spectroscopy of early-type galaxies over a range in mass.
  Sanchez-Blazquez, P., Forbes, D., Strader, J, Brodie, J., Proctor, R. 2007, MNRAS, 377, 759
• Integrated colours of Milky Way globular clusters and horizontal branch morphology.
  Smith, G., Strader, J. 2007, AN, 328, 107
• The N2K consortium. VII. Atmospheric parameters of 1907 metal-rich stars: Finding planet-search targets.
  Robinson, S., Ammons, M., Kretke, K., Strader, J., Wertheimer, J., Fischer, D., Laughlin, G. 2007, ApJS, 169, 430
• Globular cluster metallicity subpopulations in NGC 4472.
  Strader, J., Beasley, M., Brodie, J. 2007, AJ, 133, 2015. Data from paper.
• Damp mergers: Recent gaseous mergers without significant globular cluster formation?
  Forbes, D., Proctor, R., Strader, J., Brodie, J. 2007, ApJ, 659, 188

• Globular clusters in Virgo ellipticals: Unexpected results for giants and dwarfs from ACS imaging.
  Strader, J., Brodie, J., Spitler, L., Beasley, M. 2006, AJ, 132, 2333
• HST/ACS wide-field photometry of the Sombrero galaxy globular cluster system.
  Spitler, L., Larsen, S., Strader, J., Brodie, J., Forbes, D., Beasley, M. 2006, AJ, 132, 1593
• ChaMPlane discovery of candidate symbiotic binaries in Baade's and Stanek's windows.
  van den Berg, M., et al. 2006, ApJL, 647, 135
• Extragalactic globular clusters and galaxy formation.
  Brodie, J., Strader, J. 2006, ARAA, 44, 193
• The globular cluster system of the Virgo dwarf elliptical galaxy VCC 1087.
  Beasley, M., Strader, J., Brodie, J., Cenarro, A. J., Geha, M. 2006, AJ, 131, 814

• An imaging study of the globular cluster systems of NGC 1407 and NGC 1400.
  Forbes, D., Sanchez-Blazquez, P., Phan, A., Brodie, J., Strader, J., Spitler, L. 2006, MNRAS, 366, 1230
• The N2K consortium. V. Identifying very metal-rich stars with low-resolution spectra: Finding planet-search targets.
  Robinson, S., Strader, J., Ammons, M., Laughlin, G., Fischer, D. 2006, ApJ, 637, 1102
• The N2K consortium. IV. New temperatures and metallicities for 100,000+ FGK dwarfs.
  Ammons, M., Robinson, S., Strader, J., Laughlin, G., Fischer, D., Wolf, A. 2006, ApJS, 638, 1004
• The N2K consortium. III. Short-period planets orbiting HD 149143 and HD 109749.
  Fischer, D., et al. 2006, ApJ, 637, 1094
• Globular clusters in NGC 4365: New K-band imaging and a reassessment of the case for intermediate-age clusters.
  Larsen, S., Brodie, J., Strader, J. 2005, A&A, 443, 413

• The N2K consortium. II. A transiting hot saturn around HD 149026 with a large dense core.
  Sato, B., et al. 2005, ApJ, 633, 465
• Extragalactic globular clusters: Old spectroscopic ages and new views on their formation.
  Strader, J.,, Brodie, J., Cenarro, A. J., Beasley, M., Forbes, D. 2005, AJ, 130, 1315
• A hot wind from classical T Tauri Stars: TW Hydrae and T Tauri.
  Dupree, A., Brickhouse, N., Smith, G., Strader, J. 2005, ApJL, 625, L131
• Old globular clusters masquerading as young in NGC 4365?
  Brodie, J., Strader, J., Denicolo, G., Beasley, M., Cenarro, J., Larsen, S., Kuntschner, H., Forbes, D. 2005, AJ, 129, 2643
• Evolutionary history of the elliptical galaxy NGC 1052.
  Pierce, M., Brodie, J., Forbes, D., Beasley, M., Proctor, R., Strader, J. 2005, MNRAS, 358, 419

• The chemical properties of Milky Way and Andromeda globular clusters: II. Stellar popultion model predictions.
  Beasley, M., Brodie, J., Strader, J., Forbes, D., Proctor, R., Barmby, P., Huchra, J. P. 2005, AJ, 129, 1412
• The N2K consortium. I. A hot saturn planet orbiting HD 88133.
  Fischer, D., et al. 2005, ApJ, 620, 481
• Probing spectral line gradients beyond one effective radius in NGC 3610.
  Howell, J., Brodie, J., Strader, J., Forbes, D., Proctor, R. 2004, AJ, 128, 2749
• He I 10830 absorption in metal-poor red giants: Probing fast chromospheric outflows.
  Smith, G., Dupree, A., Strader, J. 2004, PASP, 116, 819
• A principal components analysis of the Lick indices of Galactic globular clusters.
  Strader, J., Brodie, J. 2004, AJ, 128, 1671

• The chemical properties of Milky Way and Andromeda globular clusters: I. A comparative study.
  Beasley, M., Brodie, J., Strader, J., Forbes, D., Proctor, R., Barmby, P., Huchra, J. 2004, AJ, 128, 1623
• Metal-poor globular clusters and galaxy formation.
  Strader, J., Brodie, J., Forbes, D. 2004, AJ, 127, 3431
• The globular cluster system of the Canis Major dwarf galaxy.
  Forbes, D., Strader, J., Brodie, J. 2004, AJ, 127, 3394
• Revisiting the globular cluster system of the merger remnant elliptical NGC 3610.
  Strader, J., Brodie, J., Forbes, D. 2004, AJ, 127, 295
• Hubble Space Telescope observations of globular cluster systems along the Hubble sequence of spiral galaxies.
  Goudfrooij, P., Strader, J., Brenneman, L., Kissler-Patig, M., Huizinga, E. 2003, MNRAS, 343, 665

• Galaxy disruption in a halo of dark matter.
  Forbes, D., Beasley, M., Bekki, K., Brodie, J., Strader, J. 2003, Science, 301, 1217
• Spectroscopy of globular clusters in the Fornax dwarf galaxy.
  Strader, J., Brodie, J., Forbes, D., Beasley, M., Huchra, J. 2003, AJ, 125, 1291
• Spectroscopy of a globular cluster in the Local Group dIrr NGC 6822.
  Strader, J., Brodie, J., Huchra, J., 2003, MNRAS, 339, 707
• Keck spectroscopy of globular clusters in the elliptical galaxy NGC 3610.
  Strader, J., Brodie, J., Schweizer, F., Larsen, S., Seitzer, P. 2003, AJ, 125, 626
• Variable stars in the core of the globular cluster M3.
  Strader, J., Everitt, H., Danford, S., 2002, MNRAS, 335, 621