Search Results - "Stephens, Ian"

Formation of Massive Protostellar Clusters—Observations of Massive 70 μm Dark Molecular Clouds by Li, Shanghuo, Zhang, Qizhou, Pillai, Thushara, Stephens, Ian W., Wang, Junzhi, Li, Fei

“…Abstract We present Submillimeter Array observations of seven massive molecular clumps that are dark in the far-infrared for wavelengths up to 70 μ m. Our…”
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Scattering-produced (sub)millimetre polarization in inclined discs: optical depth effects, near–far side asymmetry and dust settling by Yang, Haifeng, Li, Zhi-Yun, Looney, Leslie W., Girart, Josep M., Stephens, Ian W.

“…Abstract Disc polarization at (sub)millimetre wavelengths is being revolutionized by ALMA observationally, but its origin remains uncertain. Dust scattering…”
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Four annular structures in a protostellar disk less than 500,000 years old by Segura-Cox, Dominique M., Schmiedeke, Anika, Pineda, Jaime E., Stephens, Ian W., Fernández-López, Manuel, Looney, Leslie W., Caselli, Paola, Li, Zhi-Yun, Mundy, Lee G., Kwon, Woojin, Harris, Robert J.

“…Annular structures (rings and gaps) in disks around pre-main-sequence stars have been detected in abundance towards class II protostellar objects that are…”
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Can Protostellar Outflows Set Stellar Masses? by Myers, Philip C., Dunham, Michael M., Stephens, Ian W.

“…Abstract The opening angles of some protostellar outflows appear too narrow to match the expected core–star mass efficiency (SFE) = 0.3–0.5, if the outflow…”
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Dust Polarization toward Embedded Protostars in Ophiuchus with ALMA. II. IRAS 16293-2422 by Sadavoy, Sarah I., Myers, Philip C., Stephens, Ian W., Tobin, John, Kwon, Woojin, Segura-Cox, Dominique, Henning, Thomas, Commerçon, Benoît, Looney, Leslie

“…We present high-resolution (∼35 au) ALMA Band 6 1.3 mm dust polarization observations of IRAS 16293. These observations spatially resolve the dust polarization…”
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Does HL Tau disc polarization in ALMA band 3 come from radiatively aligned grains? by Yang, Haifeng, Li, Zhi-Yun, Stephens, Ian W, Kataoka, Akimasa, Looney, Leslie

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Most-likely DCF Estimates of Magnetic Field Strength by Myers, Philip C., Stephens, Ian W., Coudé, Simon

“…Abstract The Davis–Chandrasekhar–Fermi (DCF) method is widely used to evaluate magnetic fields in star-forming regions. Yet it remains unclear how well DCF…”
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A Massive Prestellar Clump Hosting No High-mass Cores by Sanhueza, Patricio, Jackson, James M., Zhang, Qizhou, Guzmán, Andrés E., Lu, Xing, Stephens, Ian W., Wang, Ke, Tatematsu, Ken'ichi

“…The infrared dark cloud (IRDC) G028.23-00.19 hosts a massive (1500 M ), cold (12 K), and 3.6-70 m IR dark clump (MM1) that has the potential to form high-mass…”
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Highly Ordered and Pinched Magnetic Fields in the Class 0 Protobinary System L1448 IRS 2 by Kwon, Woojin, Stephens, Ian W., Tobin, John J., Looney, Leslie W., Li, Zhi-Yun, van der Tak, Floris F. S., Crutcher, Richard M.

“…We have carried out polarimetric observations with the Atacama Large Millimeter/submillimeter Array toward the Class 0 protostellar system L1448 IRS 2, which…”
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ALMA Observations of Polarization from Dust Scattering in the IM Lup Protoplanetary Disk by Hull, Charles L. H., Yang, Haifeng, Li, Zhi-Yun, Kataoka, Akimasa, Stephens, Ian W., Andrews, Sean, Bai, Xuening, Cleeves, L. Ilsedore, Hughes, A. Meredith, Looney, Leslie, Pérez, Laura M., Wilner, David

“…We present 870 m ALMA observations of polarized dust emission toward the Class II protoplanetary disk IM Lup. We find that the orientation of the polarized…”
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Dust Polarization toward Embedded Protostars in Ophiuchus with ALMA. I. VLA 1623 by Sadavoy, Sarah I., Myers, Philip C., Stephens, Ian W., Tobin, John, Commerçon, Benoît, Henning, Thomas, Looney, Leslie, Kwon, Woojin, Segura-Cox, Dominique, Harris, Robert

“…We present high-resolution (∼30 au) ALMA Band 6 dust polarization observations of VLA 1623. The VLA 1623 data resolve compact ∼40 au inner disks around the two…”
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ALMA Reveals Transition of Polarization Pattern with Wavelength in HL Tau's Disk by Stephens, Ian W., Yang, Haifeng, Li, Zhi-Yun, Looney, Leslie W., Kataoka, Akimasa, Kwon, Woojin, Fernández-López, Manuel, Hull, Charles L. H., Hughes, Meredith, Segura-Cox, Dominique, Mundy, Lee, Crutcher, Richard, Rao, Ramprasad

“…The mechanism for producing polarized emission from protostellar disks at (sub)millimeter wavelengths is currently uncertain. Classically, polarization is…”
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Transanal ileal pouch-anal anastomosis: A systematic review and meta-analysis of technical approaches and clinical outcomes by Stephens, Ian J. B., Byrnes, Kevin G., Burke, John P.

“…Purpose Transanal minimally invasive surgery has theoretical advantages for ileal pouch-anal anastomosis surgery. We performed a systematic review assessing…”
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The VLA/ALMA Nascent Disk and Multiplicity (VANDAM) Survey of Orion Protostars. II. A Statistical Characterization of Class 0 and Class I Protostellar Disks by Tobin, John J., Sheehan, Patrick D., Megeath, S. Thomas, Díaz-Rodríguez, Ana Karla, Offner, Stella S. R., Murillo, Nadia M., van 't Hoff, Merel L. R., van Dishoeck, Ewine F., Osorio, Mayra, Anglada, Guillem, Furlan, Elise, Stutz, Amelia M., Reynolds, Nickalas, Karnath, Nicole, Fischer, William J., Persson, Magnus, Looney, Leslie W., Li, Zhi-Yun, Stephens, Ian, Chandler, Claire J., Cox, Erin, Dunham, Michael M., Tychoniec, ukasz, Kama, Mihkel, Kratter, Kaitlin, Kounkel, Marina, Mazur, Brian, Maud, Luke, Patel, Lisa, Perez, Laura, Sadavoy, Sarah I., Segura-Cox, Dominique, Sharma, Rajeeb, Stephenson, Brian, Watson, Dan M., Wyrowski, Friedrich

“…We have conducted a survey of 328 protostars in the Orion molecular clouds with the Atacama Large Millimeter/submillimeter Array at 0.87 mm at a resolution of…”
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ALMA's Polarized View of 10 Protostars in the Perseus Molecular Cloud by Cox, Erin G., Harris, Robert J., Looney, Leslie W., Li, Zhi-Yun, Yang, Haifeng, J. Tobin, John, Stephens, Ian

“…We present 870 m ALMA dust polarization observations of 10 young Class 0/I protostars in the Perseus Molecular Cloud. At ∼0 35 (80 au) resolution, all of our…”
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Contemporary perioperative outcomes after total abdominal colectomy for ulcerative colitis in a tertiary referral centre by Stephens, Ian J B, Murphy, Brenda, Burns, Lucy, McCawley, Niamh, McNamara, Deborah A, Burke, John P

“…Colectomy for ulcerative colitis (UC) is common despite therapeutic advances. Post-operative morbidity and mortality demonstrate an association between…”
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Low-level Carbon Monoxide Line Polarization in Two Protoplanetary Disks: HD 142527 and IM Lup by Stephens, Ian W., Fernández-López, Manuel, Li, Zhi-Yun, Looney, Leslie W., Teague, Richard

“…Abstract Magnetic fields are expected to play an important role in accretion processes for circumstellar disks. However, measuring the magnetic field…”
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Hierarchical Fragmentation in the Perseus Molecular Cloud: From the Cloud Scale to Protostellar Objects by Pokhrel, Riwaj, Myers, Philip C., Dunham, Michael M., Stephens, Ian W., Sadavoy, Sarah I., Zhang, Qizhou, Bourke, Tyler L., Tobin, John J., Lee, Katherine I., Gutermuth, Robert A., Offner, Stella S. R.

“…We present a study of hierarchical structure in the Perseus molecular cloud, from the scale of the entire cloud ( pc) to smaller clumps (∼1 pc), cores…”
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Alignment between Protostellar Outflows and Filamentary Structure by Stephens, Ian W., Dunham, Michael M., Myers, Philip C., Pokhrel, Riwaj, Sadavoy, Sarah I., Vorobyov, Eduard I., Tobin, John J., Pineda, Jaime E., Offner, Stella S. R., Lee, Katherine I., Kristensen, Lars E., Jørgensen, Jes K., Goodman, Alyssa A., Bourke, Tyler L., Arce, Héctor G., Plunkett, Adele L.

“…We present new Submillimeter Array (SMA) observations of CO(2-1) outflows toward young, embedded protostars in the Perseus molecular cloud as part of the Mass…”
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Discovery of Molecular-line Polarization in the Disk of TW Hya by Teague, Richard, Hull, Charles L. H., Guilloteau, Stéphane, Bergin, Edwin A., Dutrey, Anne, Henning, Thomas, Kuiper, Rolf, Semenov, Dmitry, Stephens, Ian W., Vlemmings, Wouter H. T.

“…Abstract We report observations of polarized line and continuum emission from the disk of TW Hya using the Atacama Large Millimeter/submillimeter Array. We…”
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