1. Judy’s contribution to globular cluster science
Raffaele Gratton
INAF – Osservatorio Astronomico di Padova, ITALY

2. Contribution to GC science: numbers
139 entries in ADS with "Cohen, J." AND "globular“:
oldest 1975, most recent 2016 (query on Jan. 11, 2017)
93 refereed papers
49 as first author
6400 citations
About 60% of Judy’s production

3. Judy’s most cited papers on GCs
292 cit: Cohen, J. G.; Persson, S. E.; Frogel, J. A. Infrared photometry, bolometric magnitudes, and effective temperatures for giants in M3, M13, M92, and M67, 1978 ApJ, 222, 165
235 cit: Frogel, J. A.; Cohen, J. G.; Persson, S. E. Globular cluster giant branches and the metallicity scale, 1983 ApJ, 275, 773
219 cit: Cohen, J. G. Abundances in globular cluster red giants. I - M3 and M13, 1978 ApJ, 223, 487
216 cit: Frogel, J. A.; Persson, S. E.; Cohen, J. G. Infrared photometry of red giants in the globular cluster 47 Tucanae, ApJ, 246, 842
214 cit: Persson, S. E.; Aaronson, M.; Cohen, J. G.; Frogel, J. A.; Matthews, K. Photometric studies of composite stellar systems. V - Infrared photometry of star clusters in the Magellanic clouds, 1983 ApJ, 266, 105
211 cit: Frogel, J. A.; Persson, S. E.; Cohen, J. G. Infrared photometry, bolometric luminosities, and effective temperatures for giant stars in 26 globular clusters, 1983 ApJS, 53, 713
186 cit: Aaronson, M.; Cohen, J. G.; Mould, J.; Malkan, M. Calibration of metallicity effects on the integrated colors of globular clusters and early-type galaxies, 1978 ApJ, 223, 824
165 cit: Cohen, J. G.; Blakeslee, J. P.; Ryzhov, A. The Ages and Abundances of a Large Sample of M87 Globular Clusters, ApJ, 496, 808
164 cit: Ramírez, S.V.; Cohen, J.G. Abundances in Stars from the Red Giant Branch Tip to Near the Main-Sequence Turnoff in M71. III. Abundance Ratios, 2002 AJ 123, 3277
157 cit: Cohen, J.G.; Meléndez, J. Abundances in a Large Sample of Stars in M3 and M13, 2005, AJ, 129, 303

4. Near IR photometry of individual stars in GCs and integrated photometry of clusters
Very strong , 16 papers; : 2 papers; 2007: 1 paper
Long term collaboration with Frogel and Persson
First derivation of near-IR photometry (JHK+CO) for individual GCs stars
Very useful for accurate determination of the physical parameters of the stars
Spread in the CO abundances in ω Cen

6. High resolution spectroscopy of GC stars - photographic Echelle spectra
Strong production : 6 papers
First attempt to derive abundances from high resolution spectra of GC stars since the pioneering work by Helfer, Wallerstein and Greeenstein (1959): First extensive survey at high spectral resolution of GC giants
Used the new echelle spectrographs at KPNO and CTIO, equipped with image tubes
Confirmation of the metallicity scale for metal-poor clusters
Overabundance of alpha-elements
First indication of a spread in Na and O abundances!!
Observation of a large spread in ω Cen (confirming photometric and ΔS results)
Some problem with the most metal-rich clusters (very low abundances)

8. Abundances for GC stars down to MS - CCD spectra
1986/1991: 2 papers; strong production : 17 papers; : 7 papers
Mainly using HIRES at Keck
Among the first abundance analysis of MS stars in GCs (with Solange Ramirez)  strong support to the multiple population scenario
Important results on the spread in the abundances of p-capture elements: the spread in dwarfs is similar to that observed in giants  indication that it likely involves the whole star  support to a multiple-generation scenario(with Michael Briley and Peter Stetson)
More recently: Large K-Ca anti-correlation within NGC2419 stars (p-capture at extremely high T) (with Evan Kirby)
First abundances from high resolution spectroscopy for metal-rich bulge clusters (NGC6553 and NGC6528)

10. HB, and peculiar stars in GCs
: 4 papers; strong production : 4 papers, mainly with Behr
Very important contribution on the composition and rotation of HB stars
Evidence of the importance of the Grundahl jump (on/off sedimentation and radiative levitation vs rotation)

12. Dynamics and abundances of GCs in other galaxies
A few papers ; strong production : 13 papers; 1 paper in 2014
Long term interest
On the abundance side, contribution (with Janet Colucci) to the development of techniques to derive abundances from integrated spectra of clusters

13. Others
Distances, Ages, and cmd of globular clusters: A few papers
Interstellar lines in the spectra of the globular clusters

14. Conclusion THANKS, JUDY
Since many years, Judy is a reference person in GC science
She obtained several basic reference results:
First extensive survey at high spectral resolution of GC giants
First indication of a spread in Na and O abundances
Among the first abundance analysis of MS stars in GCs (with Solange Ramirez)  strong support to the multiple population scenario
The spread in the abundances of p-capture elements in dwarfs is similar to that observed in giants  indication that it likely involves the whole star  support to a multiple-generation scenario (with Michael Briley and Peter Stetson)
Large K-Ca anti-correlation within NGC2419 stars (p-capture at extremely high T) (with Evan Kirby)
Evidence of the importance of the Grundahl jump (on/off sedimentation and radiative levitation vs rotation) (with Bertrand Behr)
Contribution to the development of techniques to derive abundances from integrated spectra of clusters (with Janet Colucci)
A real fundamental work!!!
THANKS, JUDY

15. Judy’s career: papers (ADS)

16. Judy’s career: citations (ADS)