Radio relics and magnetic fields in galaxy clusters

Radio relics are diffuse synchrotron sources generally located in the peripheries of galaxy clusters in merging state. According to the current leading scenario, relics trace gigantic cosmological shock waves that cross the intra-cluster medium where particle acceleration occurs. The relic/shock connection is supported by several observational facts, including the spatial coincidence between relics and shocks found in the X-rays. Under the assumptions that particles are accelerated at the shock front and are subsequently deposited and then age downstream of the shock, Markevitch et al. (2005) proposed a method to constrain the magnetic field strength in radio relics. Measuring the thickness of radio relics at different frequencies allows to derive combined constraints on the velocity of the downstream flow and on the magnetic field, which in turns determines particle aging. We elaborate this idea to infer first constraints on magnetic fields in cluster outskirts. We consider three models of particle aging and develop a geometric model to take into account the contribution to the relic transverse size due to the projection of the shock-surface on the plane of the sky. We selected three well studied radio relics in the clusters A 521, CIZA J2242.8+5301 and 1RXS J0603.3+4214. These relics have been chosen primarily because they are almost seen edge-on and because the Mach number of the shock that is associated with these relics is measured by X-ray observations, thus allowing to break the degeneracy between magnetic field and downstream velocity in the method. For the first two clusters, our method is consistent with a pure radiative aging model allowing us to derive constraints on the relics magnetic field strength. In the case of 1RXS J0603.3+4214 we find that particle life-times are consistent with a pure radiative aging model under some conditions, however we also collect evidences for downstream particle re-acceleration in the relic W-region and for a magnetic field decaying downstream in its E-region. Our estimates of the magnetic field strength in the relics in A 521 and CIZA J2242.8+5301 provide unique information on the field properties in cluster outskirts. The constraints derived for these relics, together with the lower limits to the magnetic field that we derived from the lack of inverse Compton X-ray emission from the sources, have been combined with the constraints from Faraday rotation studies of the Coma cluster. Overall results suggest that the spatial profile of the magnetic field energy density is broader than that of the thermal gas, implying that the ε_th /ε_B ratio decreases with cluster radius. Alternatively, radio relics could trace dynamically active regions where the magnetic field strength is biased high with respect to the average value in the cluster volume.

How Teresa and Maria Margaretha migrated to Nordstrand: Translation of Relics and Transformation of a German Island into a Catholic Dutch enclave in the 17th century

When on 26 May 1662 the founding first stone was laid for a new church on the island Nordstrand at the coast of Schleswig, relics of Teresa of Avila (1515-1582) and of the Dutch Carmelite abbess Maria Margaretha ab Angelis (1605-1658) were inserted. This church was built for Dutch dyke builders who were called to reconstruct the island after its destruction by flood in 1634; coming from a Catholic background and from the Dutch Republic which was at war with Spain at that time, the dyke builders and their families were guaranteed religious freedom in the Lutheran duchy of Holstein. In this paper, the reasons for the choice for the Spanish mystic Teresa of Avila and for the Dutch Carmelite abbess Maria Margaretha are discussed. The latter patroness was never beatified but had died in the smell of holiness; after her death several miracles were ascribed to her. It is understandable that migrants brought relics of their appreciated holy persons who would remind them of their homeland. The paper will first shortly introduce the two patronesses of the church. In the second part, the reasons for this choice will be discussed. Behind this translation of relics not only spiritual reasons played a role. The function of the translation of the saints was first to keep up geographical and political connections with the old country (both Spain and the Netherlands), secondly to perpetuate personal-familial relationships (esp. with Maria Margaretha), thirdly to strengthen the confessional identity in a non-Catholic environment. Fourthly the transfer brought a certain model of Christian life and reform to the new place of living, which in the second part of the 17th century became marked as “Jansenist”. The paper shows the transformation of the island into an enclave of Dutch Catholic culture.

Forgotten shrines; an account of some old Catholic halls and families in England, and of relics and memorials of the England martyrs,

Mode of access: Internet.

Visions of Joseph Smith the seer. Discoveries of ancient American relics and records /

Flake, C.J. Mormon bib.,

Catalogue of the exhibit of relics and antiquities at the Virginia Exposition, Oct. 3-Nov. 21, 1888.

Mode of access: Internet.

The flowers of literature; consisting of selections from history, biography, poetry, and romance; jeux d'esprit, traditionary relics, and essays, with translations from approved authors.

"Though the present edition ... retains, in the title-page, the name of the original editor, it varies considerably from the first edition, and may, indeed, almost be regarded as a new selection - Advertisement.

Der Heilige Rock zu Trier : und die zwanzig andern Heiligen Ungenähten Röcke ; eine historische Untersuchung /

v. 2, parts 1-3: "Die Advocaten der Trierer Rock."

Tomb M7, excavated artifact, Heart-shaped Pendant

Hunan. Changsha. Gushan; 3 17/64 in.x 2 33/64 in.x 5/32 in.; jade

Tomb M7, excavated artifact, Heart-shaped Pendant

Hunan. Changsha. Gushan; 2 41/64 in.x 2 3/64 in.x 15/64 in.; jade

Crónicas, reliquias, piedras legendarias y coronaciones en la Edad Media

Este artículo es un estudio histórico de la leyenda de la «Piedra del Destino», que fue parte del asiento del trono de coronación de los reyes de Escocia y que fue trasladada a la abadía de Westminster por el rey Eduardo de Inglaterra, que la situó bajo el trono de la coronación de los reyes de Inglaterra. La «Piedra del Destino», como muchas reliquias y antigüedades de la Edad Media, tuvo una larga historia, escrita por cronistas e historiadores. Una historia muy semejante a otras translationes de reliquias. La historia de la «Piedra del Destino» contiene ricos aspectos jurídicos, políticos y sacrales. Para comprenderlos es necesario analizar las crónicas, entendidas como textos históricos, que dan sentido a los rituales jurídicos y políticos de la Edad Media.

Gray and his friends; letters and relics in great part hitherto unpublished.

Introductory essay.--I. Unpublished letters, chiefly of foreign travel. Gray, Walpole and Ashton.--II. Correspondence and remains of Richard West.--II. Gray to John Chute.--IV. Gray to Percy and Brockett.--V. Miss Speed to Gray.--VI. Gray's notes on travel.--VII. Thoughts and verse fragments.--VIII. Collectanea and conjectures.--IX. Latin poems.

The cathedral church of Bayeux, and other historical relics in its neighborhood,

Mode of access: Internet.