610 citations · 6.3k across the 100 of their papers we have counts for
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Ion Temperatures in the Low Solar Corona: Polar Coronal Holes at Solar Minimum
Enrico Landi, Steven R. Cranmer
In the present work we use a deep-exposure spectrum taken by the SUMER spectrometer in a polar coronal hole in 1996 to measure the ion temperatures of a large number of ions at man…
Star-Planet Interactions
Evgenya Shkolnik, Suzanne Aigrain, Steven Cranmer +6
Much effort has been invested in recent years, both observationally and theoretically, to understand the interacting processes taking place in planetary systems consisting of a hot…
Plasmoids in Reconnecting Current Sheets: Solar and Terrestrial Contexts Compared
J. Lin, S. R. Cranmer, C. J. Farrugia
Magnetic reconnection plays a crucial role in violent energy conversion occurring in the environments of high electrical conductivity, such as the solar atmosphere, magnetosphere,…
Turbulence-driven Polar Winds from T Tauri Stars Energized by Magnetospheric Accretion
Steven R. Cranmer
Pre-main-sequence stars are observed to be surrounded by both accretion flows and some kind of wind or jet-like outflow. Recent work by Matt and Pudritz has suggested that if class…
On Competing Models of Coronal Heating and Solar Wind Acceleration: The Debate in '08
Steven R. Cranmer
In preparation for lively debate at the May 2008 SPD/AGU Meeting in Fort Lauderdale, this document attempts to briefly lay out my own view of the evolving controversy over how the…
Hyperdiffusion as a Mechanism for Solar Coronal Heating
A. A. van Ballegooijen, S. R. Cranmer
A theory for the heating of coronal magnetic flux ropes is developed. The dissipated magnetic energy has two distinct contributions: (1) energy injected into the corona as a result…
Improved Constraints on the Preferential Heating and Acceleration of Oxygen Ions in the Extended Solar Corona
Steven R. Cranmer, Alexander V. Panasyuk, John L. Kohl
We present a detailed analysis of oxygen ion velocity distributions in the extended solar corona, based on observations made with the Ultraviolet Coronagraph Spectrometer (UVCS) on…
Turbulence in the Solar Corona
Steven R. Cranmer
The solar corona has been revealed in the past decade to be a highly dynamic nonequilibrium plasma environment. Both the loop-filled coronal base and the extended acceleration regi…
Self-consistent Coronal Heating and Solar Wind Acceleration from Anisotropic Magnetohydrodynamic Turbulence
Steven R. Cranmer, Adriaan A. van Ballegooijen, Richard J. Edgar
We present a series of models for the plasma properties along open magnetic flux tubes rooted in solar coronal holes, streamers, and active regions. These models represent the firs…
Exoplanet-Induced Chromospheric Activity: Realistic Light Curves from Solar-type Magnetic Fields
Steven R. Cranmer, Steven H. Saar
There is growing observational evidence for some kind of interaction between stars and close-in extrasolar giant planets. Shkolnik et al. reported variability in the chromospheric…
The Structured Chromosphere and Wind of TW Hya
A. K. Dupree, E. H. Avrett, N. S. Brickhouse +2
A continuous set of echelle spectra of TW Hya, taken with the MIKE spectrograph on the Magellan2/Clay telescope at Las Campanas Observatory in April 2006 reveals systematic variati…
Winds of Main-Sequence Stars: Observational Limits and a Path to Theoretical Prediction
Steven R. Cranmer
It is notoriously difficult to measure the winds of solar-type stars. Traditional spectroscopic and radio continuum techniques are sensitive to mass loss rates at least two to thre…
A Statistical Study of Threshold Rotation Rates for the Formation of Disks around Be Stars
Steven R. Cranmer
This paper presents a detailed statistical determination of the equatorial rotation rates of classical Be stars. The rapid rotation of Be stars is likely to be linked to the ejecti…
Capabilities of UV Coronagraphic Spectroscopy for Studying the Source Regions of Solar Energetic Particles and the Solar Wind
John L. Kohl, Steven R. Cranmer, Larry D. Gardner +3
We summarize the unique capabilities of UV coronagraphic spectroscopy for determining the detailed plasma properties (e.g., density, temperature, outflow speed, composition) of the…
Why is the Fast Solar Wind Fast and the Slow Solar Wind Slow? A Survey of Geometrical Models
Steven R. Cranmer
Four decades have gone by since the discovery that the solar wind at 1 AU seems to exist in two relatively distinct states: slow and fast. There is still no universal agreement con…
On the Generation, Propagation, and Reflection of Alfven Waves from the Solar Photosphere to the Distant Heliosphere
S. R. Cranmer, A. A. van Ballegooijen
We present a comprehensive model of the global properties of Alfven waves in the solar atmosphere and fast solar wind. Linear non-WKB wave transport equations are solved from the p…
Coronal Heating versus Solar Wind Acceleration
Steven R. Cranmer
Parker's initial insights from 1958 provided a key causal link between the heating of the solar corona and the acceleration of the solar wind. However, we still do not know what fr…
New Insights into Solar Wind Physics from SOHO
Steven R. Cranmer
The Solar and Heliospheric Observatory (SOHO) was launched in December 1995 with a suite of instruments designed to answer long-standing questions about the Sun's internal structur…
New views of the solar wind with the Lambert W function
Steven R. Cranmer
This paper presents closed-form analytic solutions to two illustrative problems in solar physics that have been considered not solvable in this way previously. Both the outflow spe…
Observational Aspects of Wave Acceleration in Open Magnetic Regions
Steven R. Cranmer
This paper reviews the latest observational evidence for the existence of propagating waves in the open magnetic flux tubes of the solar corona. SOHO measurements have put tentativ…
Alfvenic Turbulence in the Extended Solar Corona: Kinetic Effects and Proton Heating
S. R. Cranmer, A. A. van Ballegooijen
We present a model of magnetohydrodynamic (MHD) turbulence in the extended solar corona that contains the effects of collisionless dissipation and anisotropic particle heating. Mea…
Solar Wind Acceleration in Coronal Holes
Steven R. Cranmer
This paper reviews the current state of our understanding of high-speed solar wind acceleration in coronal holes. Observations by SOHO, coupled with interplanetary particle measure…
Hydrodynamical Simulations of Corotating Interaction Regions and Discrete Absorption Components in Rotating O-Star Winds
S. R. Cranmer, S. P. Owocki
We present two-dimensional hydrodynamical simulations of corotating stream structure in the wind from a rotating O star, together with resulting synthetic line profiles showing dis…