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Dr Sarah Ragan
Uwch Ddarlithydd
Grŵp Seryddiaeth
Canolfan Caerdydd ar gyfer Ymchwil a Thechnoleg Astroffiseg
- Ar gael fel goruchwyliwr ôl-raddedig
Trosolwyg
Rwyf wedi bod yn aelod o staff yn yr Ysgol Ffiseg a Seryddiaeth ers 2016, ac ar hyn o bryd rwy'n Uwch-Ddarlithydd. Ers ennill fy PhD yn 2009 ym Mhrifysgol Michigan, Ann Arbor, rwyf wedi dal swyddi ymchwil yn Sefydliad Max Planck ar gyfer Seryddiaeth yn Heidelberg, Prifysgol Leeds a Phrifysgol Caerdydd. Dechreuais ar swydd academaidd yn 2018.
Mae fy ymchwil ar gamau cynnar ffurfio sêr, ac rwy'n defnyddio cyfuniad o dechnegau arsylwi a modelu i ddeall pa amodau mewn cymylau moleciwlaidd sy'n angenrheidiol ar gyfer ffurfio sêr, sydd o'r amodau hynny'n hyrwyddo ffurfio sêr màs uchel yn benodol, a beth sy'n achosi ffurfio'r cymylau moleciwlaidd yn y lle cyntaf. Mae ein hymchwil wedi dangos bod y pynciau hyn i gyd yn gysylltiedig, ac yn gysylltiedig â'r amgylchedd ehangach yn y Galaxy hefyd!
Cyhoeddiad
2024
- King, S. M. et al. 2024. CHIMPS2: 13CO J = 3→2 emission in the central molecular zone. Monthly Notices of the Royal Astronomical Society 533(1), pp. 131–142. (10.1093/mnras/stae1854)
- Priestley, F. D., Clark, P. C., Glover, S. C. O., Ragan, S. E., Feher, O., Prole, L. R. and Klessen, R. S. 2024. NEATH III: A molecular line survey of a simulated star-forming cloud. Monthly Notices of the Royal Astronomical Society 531(4), pp. 4408–4421. (10.1093/mnras/stae1442)
- Fehér, O., Ragan, S. E., Priestley, F. D., Clark, P. C. and Moore, T. J. T. 2024. N2H+(1–0) as a tracer of dense gas in and between spiral arms. Monthly Notices of the Royal Astronomical Society 530(2), pp. 1311–1327. (10.1093/mnras/stae918)
- Rigby, A. J. et al. 2024. The dynamic centres of infrared-dark clouds and the formation of cores. Monthly Notices of the Royal Astronomical Society 528(2), pp. 1172–1197. (10.1093/mnras/stae030)
2023
- Priestley, F. D., Clark, P. C., Glover, S. C. O., Ragan, S. E., Feher, O., Prole, L. R. and Klessen, R. S. 2023. NEATH – II. N2H+ as a tracer of imminent star formation in quiescent high-density gas. Monthly Notices of the Royal Astronomical Society 526(4), pp. 4952–4960. (10.1093/mnras/stad3089)
- Priestley, F. D., Clark, P. C., Glover, S. C. O., Ragan, S. E., Feher, O., Prole, L. R. and Klessen, R. S. 2023. Non-equilibrium abundances treated holistically (NEATH): the molecular composition of star-forming clouds. Monthly Notices of the Royal Astronomical Society 524(4), pp. 5971–5983. (10.1093/mnras/stad2278)
- Ahmadi, A. et al. 2023. Kinematics and stability of high-mass protostellar disk candidates at sub-arcsecond resolution. Astronomy & Astrophysics 677, article number: A171. (10.1051/0004-6361/202245580)
2022
- Wells, M. R. A. et al. 2022. ATLASGAL - star forming efficiencies and the Galactic star formation rate. Monthly Notices of the Royal Astronomical Society 516(3), pp. 4245–4255. (10.1093/mnras/stac2420)
- Neralwar, K. R. et al. 2022. The SEDIGISM survey: Molecular cloud morphology II. Integrated source properties. Astronomy & Astrophysics 664(2022), article number: A84. (10.1051/0004-6361/202142513)
- Neralwar, K. R. et al. 2022. The SEDIGISM survey: Molecular cloud morphology. Astronomy & Astrophysics 663, article number: A56. (10.1051/0004-6361/202142428)
- Urquhart, J. S. et al. 2022. ATLASGAL - evolutionary trends in high-mass star formation. Monthly Notices of the Royal Astronomical Society 510(3), pp. 3389–3407. (10.1093/mnras/stab3511)
- Colombo, D. et al. 2022. The SEDIGISM survey: the influence of spiral arms on the molecular gas distribution of the inner Milky Way. Astronomy & Astrophysics 658, pp. 1-38., article number: A54. (10.1051/0004-6361/202141287)
2021
- Anderson, M. et al. 2021. An ALMA study of hub-filament systems - I. On the clump mass concentration within the most massive cores. Monthly Notices of the Royal Astronomical Society 508(2), pp. 2964–2978. (10.1093/mnras/stab2674)
- Smith, M. W. L. et al. 2021. The HASHTAG project: The first submillimeter images of the Andromeda Galaxy from the ground.. Astrophysical Journal Supplement Series 257, article number: 52. (10.3847/1538-4365/ac23d0)
- Elia, D. et al. 2021. The Hi-GAL compact source catalogue - II. The 360° catalogue of clump physical properties. Monthly Notices of the Royal Astronomical Society 504(2), pp. 2742–2766. (10.1093/mnras/stab1038)
- Eden, D. J. et al. 2021. Characteristic scale of star formation. I. Clump formation efficiency on local scales. Monthly Notices of the Royal Astronomical Society 500(1), pp. 191-210. (10.1093/mnras/staa3188)
- Duarte Cabral, A. et al. 2021. The SEDIGISM survey: molecular clouds in the inner galaxy. Monthly Notices of the Royal Astronomical Society 500(3), pp. 3027-3049. (10.1093/mnras/staa2480)
- Urquhart, J. S. et al. 2021. SEDIGISM-ATLASGAL: dense gas fraction and star formation efficiency across the galactic disk. Monthly Notices of the Royal Astronomical Society 500(3), article number: staa2512. (10.1093/mnras/staa2512)
- Schuller, F. et al. 2021. The SEDIGISM survey: first data release and overview of the Galactic structure*. Monthly Notices of the Royal Astronomical Society 500(3), article number: staa2369. (10.1093/mnras/staa2369)
2020
- Eden, D. J. et al. 2020. CHIMPS2: survey description and 12CO emission in the Galactic centre. Monthly Notices of the Royal Astronomical Society 498(4), pp. 5936-5951. (10.1093/mnras/staa2734)
- Henshaw, J. D. et al. 2020. Ubiquitous velocity fluctuations throughout the molecular interstellar medium. Nature Astronomy 4, pp. 1064-1071. (10.1038/s41550-020-1126-z)
- Syed, J. et al. 2020. Atomic and molecular gas properties during cloud formation. Astronomy and Astrophysics 642, article number: A68. (10.1051/0004-6361/202038449)
- Wang, Y. et al. 2020. Dense gas in a giant molecular filament. Astronomy and Astrophysics 641, article number: A53. (10.1051/0004-6361/202037928)
- Beuther, H. et al. 2020. Dynamical cloud formation traced by atomic and molecular gas. Astronomy and Astrophysics 638, article number: A44. (10.1051/0004-6361/202037950)
- Mottram, J. C. et al. 2020. From clump to disc scales in W3 IRS4. Astronomy and Astrophysics 636, article number: A118. (10.1051/0004-6361/201834152)
- Wang, Y. et al. 2020. Cloud formation in the atomic and molecular phase: HI self absorption (HISA) towards a giant molecular filament. Astronomy and Astrophysics 634, article number: A139. (10.1051/0004-6361/201935866)
- Li, Z. et al. 2020. The HASHTAG project I. A survey of CO(3–2) emission from the star forming disc of M31. Monthly Notices of the Royal Astronomical Society 492(1), pp. 195-290. (10.1093/mnras/stz3409)
- Pettitt, A. R., Ragan, S. E. and Smith, M. C. 2020. Young stars as tracers of a barred-spiral Milky Way. Monthly Notices of the Royal Astronomical Society 4914(2), pp. 2162-2179. (10.1093/mnras/stz3155)
2019
- Rigby, A. J. et al. 2019. CHIMPS: physical properties of molecular clumps across the inner Galaxy. Astronomy and Astrophysics 632, article number: A58. (10.1051/0004-6361/201935236)
- Clark, P. C., Glover, S. C. O., Ragan, S. E. and Cabral, A. 2019. Tracing the formation of molecular clouds via [CII], [CI] and CO emission. Monthly Notices of the Royal Astronomical Society 486(4), pp. 4622-4637. (10.1093/mnras/stz1119)
- Henshaw, J. D. et al. 2019. ‘The Brick’ is not a brick: A comprehensive study of the structure and dynamics of the Central Molecular Zone cloud G0.253+0.016. Monthly Notices of the Royal Astronomical Society 485(2), pp. 2457-2485. (10.1093/mnras/stz471)
- Soler, J. D. et al. 2019. Histogram of oriented gradients: a technique for the study of molecular cloud formation. Astronomy and Astrophysics 622, article number: A166. (10.1051/0004-6361/201834300)
- Rugel, M. R. et al. 2019. Feedback in W49A diagnosed with radio recombination lines and models. Astronomy and Astrophysics 622, article number: A48. (10.1051/0004-6361/201834068)
2018
- Rugel, M. et al. 2018. OH absorption in the first quadrant of the Milky Way as seen by THOR. Astronomy and Astrophysics 618, article number: A159. (10.1051/0004-6361/201731872)
- Ahmadi, A. et al. 2018. Core fragmentation and Toomre stability analysis of W3(H20): A case study of the IRAM NOEMA large program CORE. Astronomy and Astrophysics 618(46), article number: A46. (10.1051/0004-6361/201732548)
- Beuther, H. et al. 2018. Fragmentation and disk formation during high-mass star formation: the IRAM NOEMA (Northern Extended Millimeter Array) large program CORE. Astronomy and Astrophysics 617, article number: A100. (10.1051/0004-6361/201833021)
- Ragan, S. E., Moore, T. J. T., Eden, D. J., Hoare, M. G., Urquhart, J. S., Elia, D. and Molinari, S. 2018. The role of spiral arms in Milky Way star formation. Monthly Notices of the Royal Astronomical Society 479(2), pp. 2361-2373. (10.1093/mnras/sty1672)
- Barnes, A. T. et al. 2018. Similar complex kinematics within two massive, filamentary infrared dark clouds?. Monthly Notices of the Royal Astronomical Society 475(4), pp. 5268-5289. (10.1093/mnras/sty173)
2017
- Marsh, K. et al. 2017. Multi-temperature mapping of dust structures throughout the Galactic Plane using the PPMAP tool with Herschel Hi-GAL data. Monthly Notices of the Royal Astronomical Society 471(3), pp. 2730-2742. (10.1093/mnras/stx1723)
- Elia, D. et al. 2017. The Hi-GAL compact source catalogue. I. The physical properties of the clumps in the inner Galaxy (−71.0 ◦ < ` < 67.0◦). Monthly Notices of the Royal Astronomical Society 471(1), pp. 100-143. (10.1093/mnras/stx1357)
2016
- Ragan, S. E., Moore, T. J. T., Eden, D. J., Hoare, M. G., Elia, D. and Molinari, S. 2016. The prevalence of star formation as a function of Galactocentric radius. Monthly Notices of the Royal Astronomical Society 462(3), pp. 3123-3129. (10.1093/mnras/stw1870)
- Beuther, H. et al. 2016. The HI/OH/Recombination line survey of the inner Milky Way (THOR). Survey overview and data release 1. Astronomy and Astrophysics -Berlin then Les Ulis- 595, article number: A32. (10.1051/0004-6361/201629143)
- Marsh, K., Ragan, S., Whitworth, A. P. and Clark, P. 2016. Evidence that widespread star formation may be underway in G0.253+016, 'The Brick'. Monthly Notices of the Royal Astronomical Society 461(1), pp. L16-L20. (10.1093/mnrasl/slw080)
- Lippok, N. et al. 2016. Earliest phases of star formation (EPoS). Dust temperature distributions in isolated starless cores. Astronomy and Astrophysics -Berlin then Les Ulis- 592, article number: A61. (10.1051/0004-6361/201525792)
- Feng, S., Beuther, H., Zhang, Q., Henning, T., Linz, H., Ragan, S. and Smith, R. 2016. Are infrared dark clouds really quiescent?. Astronomy and Astrophysics -Berlin then Les Ulis- 592, article number: A21. (10.1051/0004-6361/201526864)
- Abreu-Vicente, J., Ragan, S., Kainulainen, J., Henning, T., Beuther, H. and Johnston, K. 2016. Giant molecular filaments in the Milky Way II. the fourth Galactic quadrant. Astronomy and Astrophysics 590, article number: A131. (10.1051/0004-6361/201527674)
- Bertram, E., Glover, S., Clark, P., Ragan, S. and Klessen, R. 2016. Synthetic observations of molecular clouds in a galactic centre environment - I. Studying maps of column density and integrated intensity. Monthly Notices of the Royal Astronomical Society 455(4), pp. 3763-3778. (10.1093/mnras/stv2619)
2015
- Beuther, H., Ragan, S. E., Johnston, K., Henning, T., Hacar, A. and Kainulainen, J. T. 2015. Filament fragmentation in high-mass star formation. Astronomy and Astrophysics 584, article number: A67. (10.1051/0004-6361/201527108)
- Walsh, A. et al. 2015. A survey for hydroxyl in the THOR pilot region around W43. Monthly Notices of the Royal Astronomical Society 455(4), pp. 3494-3510. (10.1093/mnras/stv2446)
- Beuther, H. et al. 2015. Hierarchical fragmentation and collapse signatures in a high-mass starless region. Astronomy and Astrophysics 581, article number: A119. (10.1051/0004-6361/201526759)
- Bihr, S. et al. 2015. THOR: The H i, OH, Recombination line survey of the Milky Way. The pilot study: H i observations of the giant molecular cloud W43. Astronomy and Astrophysics 580, article number: A112. (10.1051/0004-6361/201425370)
- Bihr, S. et al. 2015. Kinematic and thermal structure at the onset of high-mass star formation. Astronomy and Astrophysics 579, article number: A51. (10.1051/0004-6361/201321269)
- Ragan, S. E., Henning, T., Beuther, H., Linz, H. and Zahorecz, S. 2015. Fragmentation and kinematics of dense molecular cores in the filamentary infrared-dark cloud G011.11–0.12. Astronomy and Astrophysics 573, article number: A119. (10.1051/0004-6361/201424948)
- Tobin, J. et al. 2015. Characterizing the youngest Herschel-detected protostars. I. envelope structure revealed by CARMA dust continuum observations. Astrophysical Journal 798(2), article number: 128. (10.1088/0004-637X/798/2/128)
2014
- Beuther, H. et al. 2014. Carbon in different phases ([CII], [CI], and CO) in infrared dark clouds: cloud formation signatures and carbon gas fractions. Astronomy and Astrophysics 571, article number: A53. (10.1051/0004-6361/201424757)
- Ragan, S. E., Henning, T., Tackenberg, J., Beuther, H., Johnston, K. G., Kainulainen, J. and Linz, H. 2014. Giant molecular filaments in the Milky Way. Astronomy and Astrophysics 568, article number: A73. (10.1051/0004-6361/201423401)
- Johnston, K., Beuther, H., Linz, H., Schmiedeke, A., Ragan, S. and Henning, T. 2014. The dynamics and star-forming potential of the massive Galactic centre cloud G0.253+0.016. Astronomy and Astrophysics 568, article number: A56. (10.1051/0004-6361/201423943)
- Tackenberg, J. et al. 2014. Kinematic structure of massive star-forming regions. I. accretion along filaments. Astronomy and Astrophysics 565, article number: A101. (10.1051/0004-6361/201321555)
- Wang, K. et al. 2014. Hierarchical fragmentation and differential star formation in the Galactic `Snake': infrared dark cloud G11.11-0.12. Monthly Notices of the Royal Astronomical Society 439(4), pp. 3275-3293. (10.1093/mnras/stu127)
2013
- Ragan, S., Henning, T. and Beuther, H. 2013. APEX/SABOCA observations of small-scale structure of infrared-dark clouds I. early evolutionary stages of star-forming cores. Astronomy and Astrophysics 559(Novemb), article number: A79. (10.1051/0004-6361/201321869)
- Kainulainen, J., Ragan, S., Henning, T. and Stutz, A. 2013. High-fidelity view of the structure and fragmentation of the high-mass, filamentary IRDC G11.11-0.12. Astronomy and Astrophysics 557(Septem), article number: A120. (10.1051/0004-6361/201321760)
- Beuther, H. et al. 2013. Fragmentation and dynamical collapse of the starless high-mass star-forming region IRDC 18310-4. Astronomy and Astrophysics 553(May), pp. 115., article number: A115. (10.1051/0004-6361/201220475)
- Clark, P., Glover, S. C. O., Ragan, S., Shetty, R. and Klessen, R. S. 2013. On the temperature structure of the galactic center cloud G0.253+0.016. Astrophysical Journal Letters 768(2), article number: L34. (10.1088/2041-8205/768/2/L34)
- Pitann, J. et al. 2013. G048.66-0.29: physical state of an isolated site of massive star formation. Astrophysical Journal 766(2), article number: 68. (10.1088/0004-637X/766/2/68)
- Launhardt, R. et al. 2013. The Earliest Phases of Star Formation (EPoS): a Herschel key project: the thermal structure of low-mass molecular cloud cores. Astronomy and Astrophysics 551(March), article number: A98. (10.1051/0004-6361/201220477)
2012
- Nielbock, M. et al. 2012. The Earliest Phases of Star formation (EPoS) observed with Herschel: the dust temperature and density distributions of B68. Astronomy and Astrophysics 547(Novemb), article number: A11. (10.1051/0004-6361/201219139)
- Ragan, S. et al. 2012. The Earliest Phases of Star Formation (EPoS): a Herschel key program: the precursors to high-mass stars and clusters. Astronomy and Astrophysics 547(Novemb), article number: A49. (10.1051/0004-6361/201219232)
- Ragan, S., Heitsch, F., Bergin, E. and Wilner, D. 2012. Very large array observations of ammonia in infrared-dark clouds. II. internal kinematics. Astrophysical Journal 746(2), article number: 174. (10.1088/0004-637X/746/2/174)
- Beuther, H. et al. 2012. The onset of high-mass star formation in the direct vicinity of the Galactic mini-starburst W43. Astronomy and Astrophysics 538(Februa), article number: A11. (10.1051/0004-6361/201117850)
2011
- Ragan, S., Bergin, E. and Wilner, D. 2011. Very large array observations of ammonia in infrared-dark clouds. I. column density and temperature structure. Astrophysical Journal 736(2), article number: 163. (10.1088/0004-637X/736/2/163)
2010
- Henning, T. et al. 2010. The seeds of star formation in the filamentary infrared-dark cloud G011.11-0.12. Astronomy and Astrophysics 518, article number: A95. (10.1051/0004-6361/201014635)
2009
- Gibson, D., Plume, R., Bergin, E., Ragan, S. and Evans, N. 2009. Molecular line observations of infrared dark clouds. II. physical conditions. Astrophysical Journal 705(1), pp. 123-134. (10.1088/0004-637X/705/1/123)
- Ragan, S., Bergin, E. A. and Gutermuth, R. A. 2009. Detection of structure in infrared-dark clouds with Spitzer: characterizing star formation in the molecular ring. Astrophysical Journal 698(1), pp. 324-349. (10.1088/0004-637X/698/1/324)
2006
- Ragan, S., Bergin, E., Plume, R., Gibson, D., Wilner, D., O'Brien, S. and Hails, E. 2006. Molecular line observations of infrared dark clouds: seeking the precursors to intermediate and massive star formation. Astrophysical Journal Supplement 166(2), pp. 567-584. (10.1086/506594)
Erthyglau
- King, S. M. et al. 2024. CHIMPS2: 13CO J = 3→2 emission in the central molecular zone. Monthly Notices of the Royal Astronomical Society 533(1), pp. 131–142. (10.1093/mnras/stae1854)
- Priestley, F. D., Clark, P. C., Glover, S. C. O., Ragan, S. E., Feher, O., Prole, L. R. and Klessen, R. S. 2024. NEATH III: A molecular line survey of a simulated star-forming cloud. Monthly Notices of the Royal Astronomical Society 531(4), pp. 4408–4421. (10.1093/mnras/stae1442)
- Fehér, O., Ragan, S. E., Priestley, F. D., Clark, P. C. and Moore, T. J. T. 2024. N2H+(1–0) as a tracer of dense gas in and between spiral arms. Monthly Notices of the Royal Astronomical Society 530(2), pp. 1311–1327. (10.1093/mnras/stae918)
- Rigby, A. J. et al. 2024. The dynamic centres of infrared-dark clouds and the formation of cores. Monthly Notices of the Royal Astronomical Society 528(2), pp. 1172–1197. (10.1093/mnras/stae030)
- Priestley, F. D., Clark, P. C., Glover, S. C. O., Ragan, S. E., Feher, O., Prole, L. R. and Klessen, R. S. 2023. NEATH – II. N2H+ as a tracer of imminent star formation in quiescent high-density gas. Monthly Notices of the Royal Astronomical Society 526(4), pp. 4952–4960. (10.1093/mnras/stad3089)
- Priestley, F. D., Clark, P. C., Glover, S. C. O., Ragan, S. E., Feher, O., Prole, L. R. and Klessen, R. S. 2023. Non-equilibrium abundances treated holistically (NEATH): the molecular composition of star-forming clouds. Monthly Notices of the Royal Astronomical Society 524(4), pp. 5971–5983. (10.1093/mnras/stad2278)
- Ahmadi, A. et al. 2023. Kinematics and stability of high-mass protostellar disk candidates at sub-arcsecond resolution. Astronomy & Astrophysics 677, article number: A171. (10.1051/0004-6361/202245580)
- Wells, M. R. A. et al. 2022. ATLASGAL - star forming efficiencies and the Galactic star formation rate. Monthly Notices of the Royal Astronomical Society 516(3), pp. 4245–4255. (10.1093/mnras/stac2420)
- Neralwar, K. R. et al. 2022. The SEDIGISM survey: Molecular cloud morphology II. Integrated source properties. Astronomy & Astrophysics 664(2022), article number: A84. (10.1051/0004-6361/202142513)
- Neralwar, K. R. et al. 2022. The SEDIGISM survey: Molecular cloud morphology. Astronomy & Astrophysics 663, article number: A56. (10.1051/0004-6361/202142428)
- Urquhart, J. S. et al. 2022. ATLASGAL - evolutionary trends in high-mass star formation. Monthly Notices of the Royal Astronomical Society 510(3), pp. 3389–3407. (10.1093/mnras/stab3511)
- Colombo, D. et al. 2022. The SEDIGISM survey: the influence of spiral arms on the molecular gas distribution of the inner Milky Way. Astronomy & Astrophysics 658, pp. 1-38., article number: A54. (10.1051/0004-6361/202141287)
- Anderson, M. et al. 2021. An ALMA study of hub-filament systems - I. On the clump mass concentration within the most massive cores. Monthly Notices of the Royal Astronomical Society 508(2), pp. 2964–2978. (10.1093/mnras/stab2674)
- Smith, M. W. L. et al. 2021. The HASHTAG project: The first submillimeter images of the Andromeda Galaxy from the ground.. Astrophysical Journal Supplement Series 257, article number: 52. (10.3847/1538-4365/ac23d0)
- Elia, D. et al. 2021. The Hi-GAL compact source catalogue - II. The 360° catalogue of clump physical properties. Monthly Notices of the Royal Astronomical Society 504(2), pp. 2742–2766. (10.1093/mnras/stab1038)
- Eden, D. J. et al. 2021. Characteristic scale of star formation. I. Clump formation efficiency on local scales. Monthly Notices of the Royal Astronomical Society 500(1), pp. 191-210. (10.1093/mnras/staa3188)
- Duarte Cabral, A. et al. 2021. The SEDIGISM survey: molecular clouds in the inner galaxy. Monthly Notices of the Royal Astronomical Society 500(3), pp. 3027-3049. (10.1093/mnras/staa2480)
- Urquhart, J. S. et al. 2021. SEDIGISM-ATLASGAL: dense gas fraction and star formation efficiency across the galactic disk. Monthly Notices of the Royal Astronomical Society 500(3), article number: staa2512. (10.1093/mnras/staa2512)
- Schuller, F. et al. 2021. The SEDIGISM survey: first data release and overview of the Galactic structure*. Monthly Notices of the Royal Astronomical Society 500(3), article number: staa2369. (10.1093/mnras/staa2369)
- Eden, D. J. et al. 2020. CHIMPS2: survey description and 12CO emission in the Galactic centre. Monthly Notices of the Royal Astronomical Society 498(4), pp. 5936-5951. (10.1093/mnras/staa2734)
- Henshaw, J. D. et al. 2020. Ubiquitous velocity fluctuations throughout the molecular interstellar medium. Nature Astronomy 4, pp. 1064-1071. (10.1038/s41550-020-1126-z)
- Syed, J. et al. 2020. Atomic and molecular gas properties during cloud formation. Astronomy and Astrophysics 642, article number: A68. (10.1051/0004-6361/202038449)
- Wang, Y. et al. 2020. Dense gas in a giant molecular filament. Astronomy and Astrophysics 641, article number: A53. (10.1051/0004-6361/202037928)
- Beuther, H. et al. 2020. Dynamical cloud formation traced by atomic and molecular gas. Astronomy and Astrophysics 638, article number: A44. (10.1051/0004-6361/202037950)
- Mottram, J. C. et al. 2020. From clump to disc scales in W3 IRS4. Astronomy and Astrophysics 636, article number: A118. (10.1051/0004-6361/201834152)
- Wang, Y. et al. 2020. Cloud formation in the atomic and molecular phase: HI self absorption (HISA) towards a giant molecular filament. Astronomy and Astrophysics 634, article number: A139. (10.1051/0004-6361/201935866)
- Li, Z. et al. 2020. The HASHTAG project I. A survey of CO(3–2) emission from the star forming disc of M31. Monthly Notices of the Royal Astronomical Society 492(1), pp. 195-290. (10.1093/mnras/stz3409)
- Pettitt, A. R., Ragan, S. E. and Smith, M. C. 2020. Young stars as tracers of a barred-spiral Milky Way. Monthly Notices of the Royal Astronomical Society 4914(2), pp. 2162-2179. (10.1093/mnras/stz3155)
- Rigby, A. J. et al. 2019. CHIMPS: physical properties of molecular clumps across the inner Galaxy. Astronomy and Astrophysics 632, article number: A58. (10.1051/0004-6361/201935236)
- Clark, P. C., Glover, S. C. O., Ragan, S. E. and Cabral, A. 2019. Tracing the formation of molecular clouds via [CII], [CI] and CO emission. Monthly Notices of the Royal Astronomical Society 486(4), pp. 4622-4637. (10.1093/mnras/stz1119)
- Henshaw, J. D. et al. 2019. ‘The Brick’ is not a brick: A comprehensive study of the structure and dynamics of the Central Molecular Zone cloud G0.253+0.016. Monthly Notices of the Royal Astronomical Society 485(2), pp. 2457-2485. (10.1093/mnras/stz471)
- Soler, J. D. et al. 2019. Histogram of oriented gradients: a technique for the study of molecular cloud formation. Astronomy and Astrophysics 622, article number: A166. (10.1051/0004-6361/201834300)
- Rugel, M. R. et al. 2019. Feedback in W49A diagnosed with radio recombination lines and models. Astronomy and Astrophysics 622, article number: A48. (10.1051/0004-6361/201834068)
- Rugel, M. et al. 2018. OH absorption in the first quadrant of the Milky Way as seen by THOR. Astronomy and Astrophysics 618, article number: A159. (10.1051/0004-6361/201731872)
- Ahmadi, A. et al. 2018. Core fragmentation and Toomre stability analysis of W3(H20): A case study of the IRAM NOEMA large program CORE. Astronomy and Astrophysics 618(46), article number: A46. (10.1051/0004-6361/201732548)
- Beuther, H. et al. 2018. Fragmentation and disk formation during high-mass star formation: the IRAM NOEMA (Northern Extended Millimeter Array) large program CORE. Astronomy and Astrophysics 617, article number: A100. (10.1051/0004-6361/201833021)
- Ragan, S. E., Moore, T. J. T., Eden, D. J., Hoare, M. G., Urquhart, J. S., Elia, D. and Molinari, S. 2018. The role of spiral arms in Milky Way star formation. Monthly Notices of the Royal Astronomical Society 479(2), pp. 2361-2373. (10.1093/mnras/sty1672)
- Barnes, A. T. et al. 2018. Similar complex kinematics within two massive, filamentary infrared dark clouds?. Monthly Notices of the Royal Astronomical Society 475(4), pp. 5268-5289. (10.1093/mnras/sty173)
- Marsh, K. et al. 2017. Multi-temperature mapping of dust structures throughout the Galactic Plane using the PPMAP tool with Herschel Hi-GAL data. Monthly Notices of the Royal Astronomical Society 471(3), pp. 2730-2742. (10.1093/mnras/stx1723)
- Elia, D. et al. 2017. The Hi-GAL compact source catalogue. I. The physical properties of the clumps in the inner Galaxy (−71.0 ◦ < ` < 67.0◦). Monthly Notices of the Royal Astronomical Society 471(1), pp. 100-143. (10.1093/mnras/stx1357)
- Ragan, S. E., Moore, T. J. T., Eden, D. J., Hoare, M. G., Elia, D. and Molinari, S. 2016. The prevalence of star formation as a function of Galactocentric radius. Monthly Notices of the Royal Astronomical Society 462(3), pp. 3123-3129. (10.1093/mnras/stw1870)
- Beuther, H. et al. 2016. The HI/OH/Recombination line survey of the inner Milky Way (THOR). Survey overview and data release 1. Astronomy and Astrophysics -Berlin then Les Ulis- 595, article number: A32. (10.1051/0004-6361/201629143)
- Marsh, K., Ragan, S., Whitworth, A. P. and Clark, P. 2016. Evidence that widespread star formation may be underway in G0.253+016, 'The Brick'. Monthly Notices of the Royal Astronomical Society 461(1), pp. L16-L20. (10.1093/mnrasl/slw080)
- Lippok, N. et al. 2016. Earliest phases of star formation (EPoS). Dust temperature distributions in isolated starless cores. Astronomy and Astrophysics -Berlin then Les Ulis- 592, article number: A61. (10.1051/0004-6361/201525792)
- Feng, S., Beuther, H., Zhang, Q., Henning, T., Linz, H., Ragan, S. and Smith, R. 2016. Are infrared dark clouds really quiescent?. Astronomy and Astrophysics -Berlin then Les Ulis- 592, article number: A21. (10.1051/0004-6361/201526864)
- Abreu-Vicente, J., Ragan, S., Kainulainen, J., Henning, T., Beuther, H. and Johnston, K. 2016. Giant molecular filaments in the Milky Way II. the fourth Galactic quadrant. Astronomy and Astrophysics 590, article number: A131. (10.1051/0004-6361/201527674)
- Bertram, E., Glover, S., Clark, P., Ragan, S. and Klessen, R. 2016. Synthetic observations of molecular clouds in a galactic centre environment - I. Studying maps of column density and integrated intensity. Monthly Notices of the Royal Astronomical Society 455(4), pp. 3763-3778. (10.1093/mnras/stv2619)
- Beuther, H., Ragan, S. E., Johnston, K., Henning, T., Hacar, A. and Kainulainen, J. T. 2015. Filament fragmentation in high-mass star formation. Astronomy and Astrophysics 584, article number: A67. (10.1051/0004-6361/201527108)
- Walsh, A. et al. 2015. A survey for hydroxyl in the THOR pilot region around W43. Monthly Notices of the Royal Astronomical Society 455(4), pp. 3494-3510. (10.1093/mnras/stv2446)
- Beuther, H. et al. 2015. Hierarchical fragmentation and collapse signatures in a high-mass starless region. Astronomy and Astrophysics 581, article number: A119. (10.1051/0004-6361/201526759)
- Bihr, S. et al. 2015. THOR: The H i, OH, Recombination line survey of the Milky Way. The pilot study: H i observations of the giant molecular cloud W43. Astronomy and Astrophysics 580, article number: A112. (10.1051/0004-6361/201425370)
- Bihr, S. et al. 2015. Kinematic and thermal structure at the onset of high-mass star formation. Astronomy and Astrophysics 579, article number: A51. (10.1051/0004-6361/201321269)
- Ragan, S. E., Henning, T., Beuther, H., Linz, H. and Zahorecz, S. 2015. Fragmentation and kinematics of dense molecular cores in the filamentary infrared-dark cloud G011.11–0.12. Astronomy and Astrophysics 573, article number: A119. (10.1051/0004-6361/201424948)
- Tobin, J. et al. 2015. Characterizing the youngest Herschel-detected protostars. I. envelope structure revealed by CARMA dust continuum observations. Astrophysical Journal 798(2), article number: 128. (10.1088/0004-637X/798/2/128)
- Beuther, H. et al. 2014. Carbon in different phases ([CII], [CI], and CO) in infrared dark clouds: cloud formation signatures and carbon gas fractions. Astronomy and Astrophysics 571, article number: A53. (10.1051/0004-6361/201424757)
- Ragan, S. E., Henning, T., Tackenberg, J., Beuther, H., Johnston, K. G., Kainulainen, J. and Linz, H. 2014. Giant molecular filaments in the Milky Way. Astronomy and Astrophysics 568, article number: A73. (10.1051/0004-6361/201423401)
- Johnston, K., Beuther, H., Linz, H., Schmiedeke, A., Ragan, S. and Henning, T. 2014. The dynamics and star-forming potential of the massive Galactic centre cloud G0.253+0.016. Astronomy and Astrophysics 568, article number: A56. (10.1051/0004-6361/201423943)
- Tackenberg, J. et al. 2014. Kinematic structure of massive star-forming regions. I. accretion along filaments. Astronomy and Astrophysics 565, article number: A101. (10.1051/0004-6361/201321555)
- Wang, K. et al. 2014. Hierarchical fragmentation and differential star formation in the Galactic `Snake': infrared dark cloud G11.11-0.12. Monthly Notices of the Royal Astronomical Society 439(4), pp. 3275-3293. (10.1093/mnras/stu127)
- Ragan, S., Henning, T. and Beuther, H. 2013. APEX/SABOCA observations of small-scale structure of infrared-dark clouds I. early evolutionary stages of star-forming cores. Astronomy and Astrophysics 559(Novemb), article number: A79. (10.1051/0004-6361/201321869)
- Kainulainen, J., Ragan, S., Henning, T. and Stutz, A. 2013. High-fidelity view of the structure and fragmentation of the high-mass, filamentary IRDC G11.11-0.12. Astronomy and Astrophysics 557(Septem), article number: A120. (10.1051/0004-6361/201321760)
- Beuther, H. et al. 2013. Fragmentation and dynamical collapse of the starless high-mass star-forming region IRDC 18310-4. Astronomy and Astrophysics 553(May), pp. 115., article number: A115. (10.1051/0004-6361/201220475)
- Clark, P., Glover, S. C. O., Ragan, S., Shetty, R. and Klessen, R. S. 2013. On the temperature structure of the galactic center cloud G0.253+0.016. Astrophysical Journal Letters 768(2), article number: L34. (10.1088/2041-8205/768/2/L34)
- Pitann, J. et al. 2013. G048.66-0.29: physical state of an isolated site of massive star formation. Astrophysical Journal 766(2), article number: 68. (10.1088/0004-637X/766/2/68)
- Launhardt, R. et al. 2013. The Earliest Phases of Star Formation (EPoS): a Herschel key project: the thermal structure of low-mass molecular cloud cores. Astronomy and Astrophysics 551(March), article number: A98. (10.1051/0004-6361/201220477)
- Nielbock, M. et al. 2012. The Earliest Phases of Star formation (EPoS) observed with Herschel: the dust temperature and density distributions of B68. Astronomy and Astrophysics 547(Novemb), article number: A11. (10.1051/0004-6361/201219139)
- Ragan, S. et al. 2012. The Earliest Phases of Star Formation (EPoS): a Herschel key program: the precursors to high-mass stars and clusters. Astronomy and Astrophysics 547(Novemb), article number: A49. (10.1051/0004-6361/201219232)
- Ragan, S., Heitsch, F., Bergin, E. and Wilner, D. 2012. Very large array observations of ammonia in infrared-dark clouds. II. internal kinematics. Astrophysical Journal 746(2), article number: 174. (10.1088/0004-637X/746/2/174)
- Beuther, H. et al. 2012. The onset of high-mass star formation in the direct vicinity of the Galactic mini-starburst W43. Astronomy and Astrophysics 538(Februa), article number: A11. (10.1051/0004-6361/201117850)
- Ragan, S., Bergin, E. and Wilner, D. 2011. Very large array observations of ammonia in infrared-dark clouds. I. column density and temperature structure. Astrophysical Journal 736(2), article number: 163. (10.1088/0004-637X/736/2/163)
- Henning, T. et al. 2010. The seeds of star formation in the filamentary infrared-dark cloud G011.11-0.12. Astronomy and Astrophysics 518, article number: A95. (10.1051/0004-6361/201014635)
- Gibson, D., Plume, R., Bergin, E., Ragan, S. and Evans, N. 2009. Molecular line observations of infrared dark clouds. II. physical conditions. Astrophysical Journal 705(1), pp. 123-134. (10.1088/0004-637X/705/1/123)
- Ragan, S., Bergin, E. A. and Gutermuth, R. A. 2009. Detection of structure in infrared-dark clouds with Spitzer: characterizing star formation in the molecular ring. Astrophysical Journal 698(1), pp. 324-349. (10.1088/0004-637X/698/1/324)
- Ragan, S., Bergin, E., Plume, R., Gibson, D., Wilner, D., O'Brien, S. and Hails, E. 2006. Molecular line observations of infrared dark clouds: seeking the precursors to intermediate and massive star formation. Astrophysical Journal Supplement 166(2), pp. 567-584. (10.1086/506594)
Ymchwil
Fy ymchwil: arsylwi ffurfiant sêr Galactig
Mae fy mhrif ddiddordebau ymchwil yn yr amodau sy'n angenrheidiol ar gyfer ffurfio sêr. Rwy'n cymryd rhan mewn nifer o brosiectau gyda llawer o gydweithwyr rhyngwladol. Rwy'n tynnu sylw at y prosiectau rydw i wedi bod yn eu harwain yn ddiweddar. Cysylltwch â mi os oes gennych ddiddordeb neu os hoffech holi am brosiectau posibl!
Ffurfiant seren graddfa alaeth
Mae arolygon awyrennau galactig yn ein galluogi i astudio natur ffurfiant sêr ledled y Llwybr Llaethog dros raddfeydd ciloparsec. Mae Arsyllfa Ofod Herschel wedi cynnal arolwg o'r awyren Llwybr Llaethog gyfan yn y gyfundrefn tonfedd is-goch bell. Mae'r tonfeddi hyn yn cwmpasu brig y dosbarthiad egni ysblennydd o allyriadau thermol o rawn llwch oer. Mae ffynonellau cryno ar y tonfeddi hyn yn cynrychioli'r rhanbarthau yn y Galaxy sydd â'r amodau oer, trwchus sy'n angenrheidiol ar gyfer ffurfio sêr.
Yn Ragan et al. (2016), rydym yn cyflwyno tueddiadau ar raddfa fawr yn y dosbarthiad o wrthrychau sy'n ffurfio sêr a ddatgelwyd gan yr arolwg Hi-GAL. Fel metrig syml sy'n treiddio i fynychder ffurfiant sêr mewn ffynonellau Hi-GAL, rydym yn diffinio ffracsiwn cyfanswm nifer y ffynonellau Hi-GAL gyda chymar 70 μm fel y 'ffracsiwn sy'n ffurfio sêr' neu SFF. Y SFF cymedrig yn y ddisg galactig fewnol (3.1 kpc < RGC < 8.6 kpc) yw 25 y cant. Er gwaethaf pentwr ymddangosiadol o rifau ffynhonnell ar radii sy'n gysylltiedig â breichiau troellog, nid yw'r SFF yn dangos unrhyw wyriadau sylweddol ar y radii hyn, gan nodi nad yw'r breichiau'n effeithio ar gynhyrchiant sêr clumps trwchus naill ai trwy brosesau sbarduno corfforol neu drwy effeithiau ystadegol samplau ffynhonnell fwy sy'n gysylltiedig â'r breichiau. O fewn yr ystod hon o radiws Galactocentric, gwelwn fod y SFF yn dirywio gydag RGC ar gyfradd o −0.026 ± 0.002 y ciloparsec, er gwaethaf y ffracsiwn màs nwy trwchus y gwelwyd ei fod yn gyson yn yr Galaxy fewnol. Mae hyn yn awgrymu y gallai'r SFF fod yn ddibynnol gwan ar un neu fwy o briodweddau ffisegol ar raddfa fawr yr Alaeth, megis meteleg, maes ymbelydredd, pwysau neu gneifio, fel bod is-strwythurau trwchus cymylau moleciwlaidd yn caffael rhai eiddo mewnol a etifeddwyd o'u hamgylchedd.
Ffilamentau enfawr yn y Llwybr Llaethog
Trwy gydol y Llwybr Llaethog, mae cymylau moleciwlaidd fel arfer yn ymddangos yn ffilamentaraidd mewn morffoleg ar yr hyn sy'n ymddangos fel pob graddfa bosibl. Gan ddefnyddio'r cyfoeth o ddata arolwg awyren Galactic, rydym wedi nodi ffilamentau cydlynol cyflymder ar hyd at raddfeydd maint 100-pc. Mae'r darganfyddiad hwn yn ein galluogi i ddechrau cysylltu'r cymylau ffilamentaidd hollbresennol â strwythur Galateg. Yn Ragan et al. (2014 ) rydym yn nodi ac yn nodweddu'r sampl gyntaf o ffilamentau moleciwlaidd enfawr (GMFs) yn y Galaeth. Mae llawer o GMFs wedi'u halinio'n glir â breichiau troellog ond mae rhai yn sgwâr mewn rhanbarthau rhyng-fraich o'r awyren Galateg. Rydyn ni'n gweld bod gan y GMFs yn y breichiau troellog ffracsiwn uwch o'u màs yn y strwythurau dwysaf, fel y'u gelwir yn "clymau". Mae GMFs yn labordy newydd pwysig lle gallwn gael gwell dealltwriaeth o sut mae cwmwl moleciwlaidd a ffurfiant sêr yn dibynnu ar eu hamgylchedd Galasig.
Oeri llinell strwythur cain mewn cymylau tywyll Galactig
Mae sêr yn cael eu geni yn rhanbarthau dwysaf MCs, ond mae'n ymddangos bod y broses yn aneffeithlon iawn, gyda MCs yn trosi dim ond ychydig y cant o'u cyllideb nwy yn sêr fesul amser deinamig. Mae'r prosesau ffisegol sylfaenol sy'n rheoleiddio'r gyfradd ffurfio sêr (SFR) yn yr ISM yn dal i fod yn anhysbys ac yn cael eu dadlau'n boeth, gydag ymgeiswyr yn amrywio o gythrwfl a meysydd magnetig i adborth serol. Mae dadl bellach yn deillio o'r dystiolaeth arsylwadol, er ei bod yn ymddangos bod y rhanbarthau "dwys" yn MCs yng nghymdogaeth yr haul yn esbonio'r cysylltiadau ffurfio sêr galactig a arsylwyd, mae'r un dull yn methu ag esbonio'r SFR tuag at barth moleciwlaidd canolog (CMZ) y Llwybr Llaethog. Y prif reswm dros y ddadl hon yw nad ydym yn dal i ddeall sut mae MCs yn cael eu cydosod a'u dinistrio — y ddwy broses a osododd yn y pen draw yr amserlen y gall cwmwl ffurfio sêr drosti. Y broblem yw bod carbon monocsid (CO), prif olrheiniwr strwythur a dynameg MC, ond yn sensitif i du mewn oer MCs ac nid eu hamenni, ac mae modelau yn dangos y gall CO ffurfio'n gymharol hwyr yn y broses cynulliad. Felly, mae angen tracwyr amgen a all ymchwilio i nwy yn absenoldeb CO - nwy "CO-dark" fel y'u gelwir - i wneud cynnydd pellach wrth ddeall ffurfiad a dinistr MC.
Tracwyr llinell strwythur mân (FSL) megis carbon ïoneiddio ac atomig ([CII] a [CI]) ac ocsigen atomig ([OI]) yw chwiliedydd allweddol camau cynharaf cynulliad cwmwl. Mae'r llinellau hyn yn bwysig am sawl rheswm. Yn gyntaf, gallant olrhain y trosglwyddiad dwysedd isel o nwy atomig i foleciwlaidd sy'n nodi'r ffin o'r ISM cynnes i'r cronfeydd dŵr oer y mae sêr yn ffurfio ynddynt. Yn ail, maent yn brif oeryddion ISM yn ystod y cyfnod pontio hwn, gan ddarparu ffordd i fesur egni'r ISM. Yn olaf, oherwydd gwahanol briodweddau cyffroi'r llinellau, maent yn caniatáu inni wahaniaethu rhwng gwahanol gyfundrefnau tymheredd a dwysedd yn yr ISM.
Yn Beuther, Ragan et al. (2014), rydym yn cynnal astudiaeth beilot o sampl o gymylau moleciwlaidd quiescent mewn tracwyr o bob cam carbon. Datgelodd ein hastudiaeth fod y swyddogion olrhain yn dangos amrywiaeth o ymddygiadau yn dibynnu ar eu hamgylchedd. Mewn un cwmwl (gweler y ffigur) mae'r allyriad [CII] yn dangos arwyddion diddorol o ffurfio cwmwl deinamig, gydag allyriadau cryf ar y naill ochr i'r nwy trwchus a brofir gyda CO. Gallai hyn fod yn ffurfiad cwmwl "wedi'i ddal yn y ddeddf"! Bydd ein harsylwadau SOFIA dilynol o ardal fwy yn ein helpu i ddatgysylltu'r darlun ymhellach... Cadwch tiwnio!
Addysgu
- Trefnydd modiwl Dulliau Mathemategol PX1120 ar gyfer Ffisegwyr I
- Trefnydd modiwl Technegau Arsylwadol PX2155 mewn Seryddiaeth, modiwl labordy seryddiaeth israddedig ail flwyddyn.
Bywgraffiad
Rwyf wedi bod yn aelod o staff yn yr Ysgol Ffiseg a Seryddiaeth ers 2016, ac ar hyn o bryd rwy'n Uwch-Ddarlithydd. Ers ennill fy PhD yn 2009 ym Mhrifysgol Michigan, Ann Arbor, rwyf wedi dal swyddi ymchwil yn Sefydliad Max Planck ar gyfer Seryddiaeth yn Heidelberg, Prifysgol Leeds a Phrifysgol Caerdydd. Dechreuais ar swydd academaidd yn 2018.
Mae fy ymchwil ar gamau cynnar ffurfio sêr, ac rwy'n defnyddio cyfuniad o dechnegau arsylwi a modelu i ddeall pa amodau mewn cymylau moleciwlaidd sy'n angenrheidiol ar gyfer ffurfio sêr, sydd o'r amodau hynny'n hyrwyddo ffurfio sêr màs uchel yn benodol, a beth sy'n achosi ffurfio'r cymylau moleciwlaidd yn y lle cyntaf. Mae ein hymchwil wedi dangos bod y pynciau hyn i gyd yn gysylltiedig, ac yn gysylltiedig â'r amgylchedd ehangach yn y Galaxy hefyd!
Anrhydeddau a dyfarniadau
- 2016 Marie Skłodowska-Curie Research Fellowship (Cardiff University, 2 years funding)
- 2011 Deutsche Forschungsgemeinschaft Grant (Max Planck Institut für Astronomie, 3 years funding)
- 2009 Ralph Baldwin dissertation award (University of Michigan, prize)
- 2007 Spitzer Space Telescope archival research grant (1 year funding)
- 2006 Green Bank Telescope student support grant (1 year funding)
Safleoedd academaidd blaenorol
Swyddi academaidd
- 2021 - presennol: Uwch Ddarlithydd, Prifysgol Caerdydd, Ysgol Ffiseg a Seryddiaeth, Caerdydd, DU
- 2018 - 2021 : Darlithydd, Prifysgol Caerdydd, Ysgol Ffiseg a Seryddiaeth, Caerdydd, UK
Swyddi ymchwil
- 2016 - 2018: Marie Skłodowska-Curie Fellow, Prifysgol Caerdydd, Ysgol Ffiseg a Seryddiaeth, Caerdydd, DU
- 2014 - 2016: Cynorthwy-ydd Ymchwil Ôl-ddoethurol, Prifysgol Leeds, Ysgol Ffiseg a Seryddiaeth, Leeds, UK
- 2011 - 2014: Deutsche Forschungsgemeinschaft (hunan-ariannu) Cymrawd Ôl-ddoethurol, Max Planck Insitut für Astronomie, Heidelberg, Yr Almaen
- 2010 - 2011: Ffurfiad Star and Planet cymrawd postoctoral, Max Planck Institut für Astornomie, Heidelberg, Yr Almaen
Addysg
- 2009: PhD (Seryddiaeth ac Astroffiseg) Prifysgol Michigan, Ann Arbor, MI, UDA
- 2003: BSc ( [1] Seryddiaeth, [2] Ffiseg a [3] Mathemateg) Prifysgol Drake, Des Moines, IA, UDA
Pwyllgorau ac adolygu
- Cyfarwyddwr Astudiaethau Israddedig, yr Ysgol Ffiseg a Seryddiaeth, Prifysgol Caerdydd (2021-24)
- Aelod o'r pwyllgor Tegwch, Amrywiaeth a Chynhwysiant, Ysgol Ffiseg a Seryddiaeth, Prifysgol Caerdydd (cyfredol)
- adolygydd grant, STFC
- Canolwr cyfnodolion, ApJ, A&A, MNRAS
Contact Details
RaganSE@caerdydd.ac.uk
+44 29208 74289
Adeiladau'r Frenhines - Adeilad y Gogledd, Ystafell N/2.15A, 5 The Parade, Heol Casnewydd, Caerdydd, CF24 3AA
+44 29208 74289
Adeiladau'r Frenhines - Adeilad y Gogledd, Ystafell N/2.15A, 5 The Parade, Heol Casnewydd, Caerdydd, CF24 3AA
Themâu ymchwil
Arbenigeddau
- Gwyddor data
- Gwyddorau seryddol
- Offeryniaeth seryddol
- Seryddiaeth galactig