218 research outputs found
Art, Power and Knowledge: Claiming Public Space in Tunisia
Charles Tripp argues that through artistic interventions â graffiti, visual street art, performances, demonstrations, banners, slogans â citizens have appropriated the public
sphere. Despite the monitoring of political dissent through persuasion or coercion,
an activist public has created highly visible public spaces, assisted and encouraged
by citizen artists. They have generated debates and have helped to give substance to
competing visions of the republic
Battlefields of the Republic - the struggle for public space in Tunisia
This paper argues that the Tunisian revolutionary moment of 2011 and its aftermath have opened up spaces that are capable of providing a framework for the agonistic politics associated with democratic possibility. Insurgent public space, an emerging plural public, as well as adversarial contests over the constitution of the republic display features that may help to build âconflictual consensusâ as part of a democratic future. These possibilities are constantly being re-enacted by Tunisians whose disagreements are real enough, but whose struggles are also establishing the boundaries of an emerging political field, loosely thought of as the âTunisian Republicâ. This is a bold and challenging undertaking, with potentially revolutionary implications, but it is also a precarious enterprise, given the forces that may yet threaten to encroach on public space and on the rights of the citizen
UV Absorption Lines from High-Velocity Gas in the Vela Supernova Remnant: New insights from STIS Echelle Observations of HD72089
The star HD72089 is located behind the Vela supernova remnant and shows a
complex array of high and low velocity interstellar absorption features arising
from shocked clouds. A spectrum of this star was recorded over the wavelength
range 1196.4 to 1397.2 Angstroms at a resolving power lambda/Delta lambda =
110,000 and signal-to-noise ratio of 32 by STIS on the Hubble Space Telescope.
We have identified 7 narrow components of C I and have measured their relative
populations in excited fine-structure levels. Broader features at heliocentric
velocities ranging from -70 to +130 km/s are seen in C II, N I, O I, Si II, S
II and Ni II. In the high-velocity components, the unusually low abundances of
N I and O I, relative to S II and Si II, suggest that these elements may be
preferentially ionized to higher stages by radiation from hot gas immediately
behind the shock fronts.Comment: 11 pages, 2 figures, Latex. Submitted for the special HST ERO issue
of the Astrophysical Journal Letter
Back to the future : the Arab uprisings and state (re)formation in the Arab world
This article contributes to debates that aim to go beyond the âdemocratizationâ and âpost-democratizationâ paradigms to understand change and continuity in Arab politics. In tune with calls to focus on the actualities of political dynamics, the article shows that the literatures on State Formation and Contentious Politics provide useful theoretical tools to understand change/continuity in Arab politics. It does so by examining the impact of the latest Arab uprisings on state formation trajectories in Iraq and Syria. The uprisings have aggravated a process of regime erosion â which originated in post-colonial state-building attempts â by mobilizing sectarian and ethnic identities and exposing the counties to geo-political rivalries and intervention, giving rise to trans-border movements, such as ISIS. The resulting state fragmentation has obstructed democratic transition in Syria and constrained its consolidation in Iraq.PostprintPeer reviewe
The Quasar / Galaxy Pair PKS 1327-206 / ESO 1327-2041: Absorption Associated with a Recent Galaxy Merger
We present HST/WFPC2 broadband and ground-based Halpha images, H I 21-cm
emission maps, and low-resolution optical spectra of the nearby galaxy ESO
1327-2041, which is located 38 arcsec (14 kpc in projection) west of the quasar
PKS 1327-206. Our HST images reveal that ESO 1327-2041 has a complex optical
morphology, including an extended spiral arm that was previously classified as
a polar ring. Our optical spectra show Halpha emission from several H II
regions in this arm located ~5 arcsec from the quasar position (~2 kpc in
projection) and our ground-based Halpha images reveal the presence of several
additional H II regions in an inclined disk near the galaxy's center.
Absorption associated with ESO 1327-2041 is found in H I 21-cm, optical, and
near-UV spectra of PKS 1327-206. We find two absorption components at cz = 5255
and 5510 km/s in the H I 21-cm absorption spectrum, which match the velocities
of previously discovered metal-line components. We attribute the 5510 km/s
absorber to disk gas in the extended spiral arm and the 5255 km/s absorber to
high-velocity gas that has been tidally stripped from the disk of ESO
1327-2041. The complexity of the galaxy/absorber relationships for these very
nearby H I 21-cm absorbers suggests that the standard view of high redshift
damped Lyman-alpha absorbers is oversimplified in many cases.Comment: Replaced with accepted version; 16 page
Quenched Cold Accretion of a Large Scale Metal-Poor Filament due to Virial Shocking in the Halo of a Massive z=0.7 Galaxy
Using HST/COS/STIS and HIRES/Keck high-resolution spectra, we have studied a
remarkable HI absorbing complex at z=0.672 toward the quasar Q1317+277. The HI
absorption has a velocity spread of 1600 km/s, comprises 21 Voigt profile
components, and resides at an impact parameter of D=58 kpc from a bright, high
mass [log(M_vir/M_sun) ~ 13.7] elliptical galaxy that is deduced to have a 6
Gyr old, solar metallicity stellar population. Ionization models suggest the
majority of the structure is cold gas surrounding a shock heated cloud that is
kinematically adjacent to a multi-phase group of clouds with detected CIII, CIV
and OVI absorption, suggestive of a conductive interface near the shock. The
deduced metallicities are consistent with the moderate in situ enrichment
relative to the levels observed in the z ~ 3 Ly-alpha forest. We interpret the
HI complex as a metal-poor filamentary structure being shock heated as it
accretes into the halo of the galaxy. The data support the scenario of an early
formation period (z > 4) in which the galaxy was presumably fed by cold-mode
gas accretion that was later quenched via virial shocking by the hot halo such
that, by intermediate redshift, the cold filamentary accreting gas is
continuing to be disrupted by shock heating. Thus, continued filamentary
accretion is being mixed into the hot halo, indicating that the star formation
of the galaxy will likely remain quenched. To date, the galaxy and the HI
absorption complex provide some of the most compelling observational data
supporting the theoretical picture in which accretion is virial shocked in the
hot coronal halos of high mass galaxies.Comment: 20 pages, 9 figures, submitted to Ap
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