Search Publications
Herschel Far-infrared Photometric Monitoring of Protostars in the Orion Nebula Cluster
Billot, N.; Megeath, S. T.; Morales-Calderón, M. +2 more
We have obtained time series observations of the Orion Nebula Cluster at 70 µm and 160 µm from the Herschel/PACS Photometer. This represents the first wide-field far-infrared photometric monitoring of a young star-forming region. The acquired 35' × 35' maps show complex extended structures, with unprecedented detail, that trace the int…
Solar Rotation Effects on the Heliosheath Flow near Solar Minima
Pogorelov, Nikolai V.; Borovikov, Sergey N.; Ebert, Robert W.
The interaction between fast and slow solar wind (SW) due to the Sun's rotation creates corotating interaction regions (CIRs), which further interact with each other creating complex plasma structures at large heliospheric distances. We investigate the global influence of CIRs on the SW flow in the inner heliosheath between the heliospheric termin…
The 3.3 µm Polycyclic Aromatic Hydrocarbon Emission as a Star Formation Rate Indicator
Inami, Hanae; Nakagawa, Takao; Oyabu, Shinki +13 more
Polycyclic aromatic hydrocarbon (PAH) emission features dominate the mid-infrared spectra of star-forming galaxies and can be useful to calibrate star formation rates (SFRs) and diagnose ionized states of grains. However, the PAH 3.3 µm feature has not been studied as much as other PAH features since it is weaker than others and resides outs…
Disk-resolved photometry of Asteroid (2867) Steins
Jorda, L.; Lamy, P. L.; Keller, H. U. +2 more
We present a new method to perform disk-resolved photometry in order to investigate the intrinsic photometric properties of the surface of small Solar System bodies. We adopt the standard approach where a shape model is combined with a photometric formalism - in practise the Hapke formalism - to remove the effects of topography and recover the pho…
Inflow direction of interstellar neutrals deduced from pickup ion measurements at 1 AU
Galvin, Antoinette B.; Wimmer-Schweingruber, Robert F.; Bochsler, Peter +4 more
Observations of interstellar pickup ions inside the heliosphere provide an indirect method to access information on the surrounding interstellar medium. The so-called pickup ion focusing cone and pickup ion crescent, which show an imprint of the related longitudinal distribution of interstellar neutrals in form of two overabundances on the down- a…
Pc2 EMIC waves generated high off the equator in the dayside outer magnetosphere
Liu, Y. H.; Fraser, B. J.; Menk, F. W.
It is generally accepted that electromagnetic ion cyclotron (EMIC) waves are generated around the equatorial regions and propagate toward the high latitude ionospheres in both hemispheres. Here we describe a prolonged EMIC wave event in the Pc2 (0.1-0.2 Hz) frequency band above the He+ cyclotron frequency detected by the four Cluster sa…
Comparison of star formation rates from Hα and infrared luminosity as seen by Herschel
Kneib, J. -P.; Berta, S.; Magnelli, B. +56 more
We empirically MD test the relation between the SFR(LIR) derived from the infrared luminosity, LIR, and the SFR(Hα) derived from the Hα emission line luminosity using simple conversion relations. We use a sample of 474 galaxies at z = 0.06-0.46 with both Hα detection [from 20k redshift Cosmological Evolution (zCOSMOS) survey]…
The Connection between 3.3 µm Polycyclic Aromatic Hydrocarbon Emission and Active Galactic Nucleus Activity
Imanishi, Masatoshi; Kim, Ji Hoon; Woo, Jong-Hak +1 more
We investigate the connection between starburst and active galactic nucleus (AGN) activity by comparing 3.3 µm polycyclic aromatic hydrocarbon (PAH) emission with AGN properties. Utilizing the slitless spectroscopic capability of the AKARI space telescope, we observe a moderate-luminosity Type I AGN at z ~ 0.4 to measure global starburst act…
Coronal Mass Ejections from Magnetic Systems Encompassing Filament Channels Without Filaments
Pevtsov, Alexei A.; Panasenco, Olga; Martin, Sara F.
Well-developed filament channels may be present in the solar atmosphere even when there is no trace of filament material inside them. Such magnetic systems with filament channels without filaments can result in coronal mass ejections that might appear to have no corresponding solar surface source regions. In this case study, we analyze CMEs on 9 A…
Ionized gas diagnostics from protoplanetary discs in the Orion nebula and the abundance discrepancy problem
Tsamis, Y. G.; Henney, W. J.; García-Rojas, J. +5 more
We present results from integral field spectroscopy of a field located near the Trapezium Cluster using the Potsdam Multi-Aperture Spectrophotometer (PMAS). The observed field contains a variety of morphological structures: five externally ionized protoplanetary discs (also known as proplyds), the high-velocity jet HH 514 and a bowshock. Spatial d…