Student Recital (April 26, 2012)

Adagio and Allegro, Op. 70 / Robert Schumann Susan Blazejewski, viola Prelude in C minor, BWV 847 / Johann Sebastian Bach Important Event, Op. 15, No. 6 / Robert Schumann Carl Hollant, piano Sonatina for Trombone and Piano / Bryan Kelly Agitato Daniel Hatchfield, trombone Carl Hollant, piano Suite No. 1 in E minor, BWV 996 / J. S. Bach Prelude Jeremy Place, guitar Sonata in a minor, BWV 1013 / J. S. Bach Allemande Amethyst Lambert, flute Pie Jesu from Requiem in D minor, Op. 48 / Gabriel Fauré Mi Choe, soprano Sonata No. 3, Op. 1, No. 12, HWV 370 / George Frideric Handel arr. Sigurd Rascher Adagio Allegro Mackenzie Leahy, alto saxophone Fantasia / Sylvius Leopold Weiss Nicholas Rice, guitarhttps://vc.bridgew.edu/student_concerts/1020/thumbnail.jp

CMZoom IV. Incipient High-Mass Star Formation Throughout the Central Molecular Zone

In this work, we constrain the star-forming properties of all possible sites of incipient high-mass star formation in the Milky Way's Galactic Center. We identify dense structures using the CMZoom 1.3mm dust continuum catalog of objects with typical radii of $\sim$0.1pc, and measure their association with tracers of high-mass star formation. We incorporate compact emission at 8, 21, 24, 25, and 70um from MSX, Spitzer, Herschel, and SOFIA, catalogued young stellar objects, and water and methanol masers to characterize each source. We find an incipient star formation rate (SFR) for the CMZ of ~0.08 Msun yr^{-1} over the next few 10^5 yr. We calculate upper and lower limits on the CMZ's incipient SFR of ~0.45 Msun yr^{-1} and ~0.05 Msun yr^{-1} respectively, spanning between roughly equal to and several times greater than other estimates of CMZ's recent SFR. Despite substantial uncertainties, our results suggest the incipient SFR in the CMZ may be higher than previously estimated. We find that the prevalence of star formation tracers does not correlate with source volume density, but instead ~75% of high-mass star formation is found in regions above a column density ratio (N_{SMA}/N_{Herschel}) of ~1.5. Finally, we highlight the detection of ``atoll sources'', a reoccurring morphology of cold dust encircling evolved infrared sources, possibly representing HII regions in the process of destroying their envelopes.Comment: Accepted for publication in Ap

CMZoom: Survey Overview and First Data Release

We present an overview of the CMZoom survey and its first data release. CMZoom is the first blind, high-resolution survey of the Central Molecular Zone (CMZ; the inner 500 pc of the Milky Way) at wavelengths sensitive to the pre-cursors of high-mass stars. CMZoom is a 500-hour Large Program on the Submillimeter Array (SMA) that mapped at 1.3 mm all of the gas and dust in the CMZ above a molecular hydrogen column density of 10^23 cm^-2 at a resolution of ~3" (0.1 pc). In this paper, we focus on the 1.3 mm dust continuum and its data release, but also describe CMZoom spectral line data which will be released in a forthcoming publication. While CMZoom detected many regions with rich and complex substructure, its key result is an overall deficit in compact substructures on 0.1 - 2 pc scales (the compact dense gas fraction: CDGF). In comparison with clouds in the Galactic disk, the CDGF in the CMZ is substantially lower, despite having much higher average column densities. CMZ clouds with high CDGFs are well-known sites of active star formation. The inability of most gas in the CMZ to form compact substructures is likely responsible for the dearth of star formation in the CMZ, surprising considering its high density. The factors responsible for the low CDGF are not yet understood but are plausibly due to the extreme environment of the CMZ, having far-reaching ramifications for our understanding of the star formation process across the cosmos.Comment: Accepted for Publication in ApJ

CMZoom III: Spectral Line Data Release

We present an overview and data release of the spectral line component of the SMA Large Program, \textit{CMZoom}. \textit{CMZoom} observed $^{12}$CO(2-1), $^{13}$CO(2-1) and C$^{18}$O(2-1), three transitions of H$_{2}$CO, several transitions of CH$_{3}$OH, two transitions of OCS and single transitions of SiO and SO, within gas above a column density of N(H$_2$)$\ge 10^{23}$\,cm$^{-2}$ in the Central Molecular Zone (CMZ; inner few hundred pc of the Galaxy). We extract spectra from all compact 1.3\,mm \emph{CMZoom} continuum sources and fit line profiles to the spectra. We use the fit results from the H$_{2}$CO 3(0,3)-2(0,2) transition to determine the source kinematic properties. We find $\sim 90$\% of the total mass of \emph{CMZoom} sources have reliable kinematics. Only four compact continuum sources are formally self-gravitating. The remainder are consistent with being in hydrostatic equilibrium assuming that they are confined by the high external pressure in the CMZ. Based on the mass and density of virially bound sources, and assuming star formation occurs within one free-fall time with a star formation efficiency of $10\% - 75\%$, we place a lower limit on the future embedded star-formation rate of $0.008 - 0.06$\,M$_{\odot}$\,yr$^{-1}$. We find only two convincing proto-stellar outflows, ruling out a previously undetected population of very massive, actively accreting YSOs with strong outflows. Finally, despite having sufficient sensitivity and resolution to detect high-velocity compact clouds (HVCCs), which have been claimed as evidence for intermediate mass black holes interacting with molecular gas clouds, we find no such objects across the large survey area.Comment: 44 pages, 41 figure

Student Recital (April 1, 2011)

Fairest Isle from King Arthur, Z. 628 / Henry Purcell Stuart Cabral, counter tenor Must the winter come so soon? / Samuel Barber Diane M. Card, alto Four Short Narratives / Neal Corwell 1. Morning 3. Dusk Andrew Shaw, euphonium Alma del Core / Antonio Caldara Alison Kenney, soprano Sonata / Paul Hindemith Allegro moderato maestoso Daniel Hatchfield, trombonehttps://vc.bridgew.edu/student_concerts/1007/thumbnail.jp

Outstanding Student Recital & Awards Ceremony (Feb. 2012)

Improvisation and Caprice / Eugene Bozza Sean Every, alto saxophone Morceau Symphonique, Op.88 / Alexander Guilmant Charles Sherwin, euphonium Quia respexit / Johann Sebastian Bach from Magnificat, BWV 243 Stuart Cabral, countertenor O Ma Lyre Immortelle from Sapho / Charles Gounod Diane Card, alto Habanera from Carmen / George Bizet Diane Card, alto Barcarolle (Belle nuit, ô nuit d\u27amour) / Jacques Offenbach Stuart Cabral, countertenor Diane Card, alto Prelude, No. 4 / Heitor Villa-Lobos Nicholas Rice, guitar Waltz in B minor, Op. 60, No. 2 / Frédéric Chopin Carl Hollant, piano Variations on the Carnival of Venice / arr. Jean-Baptiste Arban Daniel Hatchfield, trombonehttps://vc.bridgew.edu/student_concerts/1001/thumbnail.jp

Student Recital: Daniel Hatchfield, Trombone (October 23, 2012)

Sonata No. 4 in G minor / Benedetto Marcello Adagio Allegro Largo Allegro T-Bone Concerto / Johan de Meij Rare Medium Well done Play “A” To Start / Matt Ahrens Daniel Hatchfield and Matt Ahrens World Premier Night on Bald Mountain / Modest Mussorgsky arr. by Charles Small Hungarian Dance No. 5, WoO1 / Johannes Brahms arr. by Robert Elkjer Roy Campbell, Jared Cowell, Peter Griffin, Daniel Hatchfield, Nathanial Karahalis, Kevin Kardel, Becca Patterson, Donald Running, Chuck Sherwin Posaunenstadt! / Eric Ewazen Roy Campbell, Jared Cowell, Peter Griffin, Daniel Hatchfield, Nathaniel Karahalis, Kevin Kardel, Sage Lewis, Becca Patterson, Donald Running, Matt Ahrens, Chuck Sherwin, Kevin Torreshttps://vc.bridgew.edu/student_concerts/1026/thumbnail.jp

CMZoom. IV. Incipient High-mass Star Formation throughout the Central Molecular Zone

In this work, we constrain the star-forming properties of all possible sites of incipient high-mass star formation in the Milky Way’s Galactic Center. We identify dense structures using the CMZoom 1.3 mm dust continuum catalog of objects with typical radii of ∼0.1 pc, and measure their association with tracers of high-mass star formation. We incorporate compact emission at 8, 21, 24, 25, and 70 μ m from the Midcourse Space Experiment, Spitzer, Herschel, and SOFIA, cataloged young stellar objects, and water and methanol masers to characterize each source. We find an incipient star formation rate (SFR) for the Central Molecular Zone (CMZ) of ∼0.08 M _⊙ yr ^−1 over the next few 10 ^5 yr. We calculate upper and lower limits on the CMZ’s incipient SFR of ∼0.45 and ∼0.05 M _⊙ yr ^−1 ,respectively, spanning roughly equal to and several times greater than other estimates of CMZ’s recent SFR. Despite substantial uncertainties, our results suggest the incipient SFR in the CMZ may be higher than previously estimated. We find that the prevalence of star formation tracers does not correlate with source volume density, but instead ≳75% of high-mass star formation is found in regions above a column density ratio ( N _SMA / N _Herschel ) of ∼1.5. Finally, we highlight the detection of atoll sources , a reoccurring morphology of cold dust encircling evolved infrared sources, possibly representing H ii regions in the process of destroying their envelopes

Student Recital (April 15, 2011)

Two, As One, In Three / John LaPorta Interplay / J. LaPorta Daniel Hatchfield, trombone Andrew Shaw, euphonium Suite No. 3 in C / Johann Sebastian Bach 1. Prelude Susan Blazejewski, viola Piano Sonata No. 2, Op. 31 / Dianne Goolkasian Rahbee) 1. Allegro maestoso Kurumi Ueno, piano Dank sei Dir, Herr / Georg Friedrich Handel If you’ve only got a moustache / Stephen Collins Foster Patrick McMahon, bass Sonata for Flute / Paul Hindemith II. Sehr langsam Deidre Balunas, flute Black is the Color of My True Love’s Hair / John Jacob Niles Noh-Kyung Park, soprano Two Hues of Blue / Lenny Niehaus 1. Moderate Blues Sean Every, alto saxophone Pieta, Signore / Alessandro Stradella Ave Maria / C. Gounod Joseph Steinkrauss, baritone El Testamen de N’amelia / Miguel Llobet Ian Timpany, guitar Vanilla Ice Cream / Jerry Bock Alison Kenney, soprano Lied der Mignon, Op. 62 / Franz Schubert Katie Sprusansky, mezzo soprano Oboe Concerto in C minor / Benedetto Marcello III. Allegro James-ace Thackston, soprano saxophone Trio in C Major for Two Violins and Viola, Op. 87 / Ludwig Van Beethoven 1. Allegro Chelsea White, violin I Elizabeth Smith, violin II Carla Mason, violin III Gail Columbo, violin IV Susan Blazejewski, violahttps://vc.bridgew.edu/student_concerts/1008/thumbnail.jp