726 research outputs found

    Chiaroscuro and the Quest for Optimal Resonance

    Get PDF
    The author discusses chiaroscuro, which refers to the balance of brilliance and warmth in the timbre of the singing voice. He offers exercises and approaches to help singers discover and foster optimal resonance in their voices. Resonance is explained, techniques for recognizing optimal chiaroscuro are shared, and methods of digital palpitation of the buccal and laryngeal regions to tune the resonance tract are detailed

    Discovery of 11 New T Dwarfs in the Two Micron All-Sky Survey, Including a Possible L/T Transition Binary

    Get PDF
    We present the discovery of 11 new T dwarfs, found during the course of a photometric survey for mid-to-late T dwarfs in the 2MASS Point Source Catalog and from a proper motion selected sample of ultracool dwarfs in the 2MASS Working Database. Using the NASA Infrared Telescope Facility SpeX spectrograph, we obtained low-resolution (R~150) spectroscopy, allowing us to derive near-infrared spectral types of T2-T8. One of these new T dwarfs, 2MASS J13243559+6358284, was also discovered independently by Metchev et al., in prep. This object is spectroscopically peculiar and possibly a binary and/or very young (<300 Myr). We specifically attempted to model the spectrum of this source as a composite binary to reproduce its peculiar spectral characteristics. The latest-type object in our sample is a T8 dwarf, 2MASS J07290002-3954043, now one of the four latest-type T dwarfs known. All 11 T dwarfs are nearby given their spectrophotometric distance estimates, with 1 T dwarf within 10 pc and 8 additional T dwarfs within 25 pc, if single. These new additions increase the 25 pc census of T dwarfs by ~14%. Their proximity offers an excellent opportunity to probe for companions at closer separations than are possible for more distant T dwarfs.Comment: 45 pages, 9 figures, 9 tables. Published in AJ. Replacement: Fixed typos in 3 tables (some reported photometry was from the 2MASS Working Database instead of the 2MASS All Sky Catalog) and updated Fig.

    A Candidate Wide Brown Dwarf Binary in the Argus Association: 2MASS J14504216-7841413 and 2MASS J14504113-7841383

    Get PDF
    [not part of Research Note] We report the discovery of a widely-separated low-mass binary as a candidate member of the ∼\sim40 Myr Argus Association. Resolved imaging and astrometry with 2MASS and LDSS-3 reveal a common proper motion pair of red sources separated by 4.23''±\pm0.11'', with the secondary roughly one magnitude fainter at ii, zz and JJ. Resolved spectroscopy indicates component types of M8pec and M9pec, the peculiarities arising from weak Na I and strong VO absorption characteristic of low gravity sources. With its small proper motion and estimated 75±\pm25 pc distance, the BANYAN II tool indicates a membership probability of 93% in Argus, which would be consistent with a pair of brown dwarfs of mass ∼\sim0.04 M⊙_{\odot} separated by ∼\sim300 AU.Comment: 3 pages, 1 figure, accepted to Research Notes of the AA

    Faculty Recital: Adam Kirkpatrick, tenor with Benjamin Wadsworth, piano

    Get PDF
    Kennesaw State University School of Music presents Adam Kirkpatrick, tenor with Benjamin Wadsworth, piano.https://digitalcommons.kennesaw.edu/musicprograms/1366/thumbnail.jp

    Dwarf Archives: A Compendium of M, L, and T Dwarf Data

    Get PDF
    Dwarf Archives is an online archive containing astrometric, photometric, and spectroscopic information for all known L and T dwarfs (over 650 objects), as well as a select sample of over 500 M dwarfs. In this paper, we describe the specific data available in the archive, the interface for searching through it and discuss plans for future updates

    The Collapse of the Wien Tail in the Coldest Brown Dwarf? Hubble Space Telescope Near-Infrared Photometry of WISE J085510.83-071442.5

    Get PDF
    We present Hubble Space Telescope (HST) near-infrared photometry of the coldest known brown dwarf, WISE J085510.83−-071442.5 (WISE 0855−-0714). WISE 0855−-0714 was observed with the Wide Field Camera 3 (WFC3) aboard HST using the F105W, F125W, and F160W filters, which approximate the YY, JJ, and HH near-infrared bands. WISE 0855−-0714 is undetected at F105W with a corresponding 2σ\sigma magnitude limit of ∼\sim26.9. We marginally detect WISE 0855−-0714 in the F125W images (S/N ∼\sim4), with a measured magnitude of 26.41 ±\pm 0.27, more than a magnitude fainter than the J−J-band magnitude reported by Faherty and coworkers. WISE J0855−-0714 is clearly detected in the F160W band, with a magnitude of 23.90 ±\pm 0.02, the first secure detection of WISE 0855−-0714 in the near-infrared. Based on these data, we find that WISE 0855−-0714 has extremely red F105W−-F125W and F125W−-F160W colors relative to other known Y dwarfs. We find that when compared to the models of Saumon et al. and Morley et al., the F105W−-F125W and F125W−-F160W colors of WISE 0855−-0714 cannot be accounted for simultaneously. These colors likely indicate that we are seeing the collapse of flux on the Wien tail for this extremely cold object.Comment: Accepted for publication in ApJ Letter

    Teaching Lower Laryngeal Position with EMG Biofeedback

    Get PDF
    The authors explore new and innovative ways to teach singers how to maintain the lower laryngeal position while singing - a component of classical singing technique that many consider essential to achieving a vibrant, focused, and resonant tone

    Low-mass Tertiary Companions to Spectroscopic Binaries. I. Common Proper Motion Survey for Wide Companions Using 2MASS

    Get PDF
    We report the first results of a multi-epoch search for wide (separations greater than a few tens of AU), low-mass tertiary companions of a volume-limited sample of 118 known spectroscopic binaries within 30 pc of the Sun, using the Two Micron All Sky Survey Point Source Catalog and follow-up observations with the KPNO and CTIO 4 m telescopes. Note that this sample is not volume complete but volume limited, and, thus, there is incompleteness in our reported companion rates. We are sensitive to common proper motion companions with separations from roughly 200 AU to 10,000 AU (~10ˮ → ~ 10'). From 77 sources followed-up to date, we recover 11 previously known tertiaries, 3 previously known candidate tertiaries, of which 2 are spectroscopically confirmed and 1 rejected, and 3 new candidates, of which 2 are confirmed and 1 rejected. This yields an estimated wide tertiary fraction of 19.5^(+5.2)_(–3.7)%. This observed fraction is consistent with predictions set out in star formation simulations where the fraction of wide, low-mass companions to spectroscopic binaries is >10%
    • …
    corecore