The Fox Expedition in Search of Franklin : A Documentary Trail

A portfolio of contemporary documents relating to the Fox expedition in search of Sir John Franklin has recently been found. It contained 14 personal letters written to Captain F.L. M'Clintock by Lady Jane Franklin and her niece, Sophia Cracroft; newspaper clippings of long letters from explorer John Rae and Allen Young, third officer on the Fox; and a drawing. With one exception, these documents are being introduced to scholars for the first time. Newly discovered is Lady Jane Franklin's offer of command of the Fox to Captain F.L. M'Clintock. The documents, now in the author's possession, affirm Lady Franklin's thoroughgoing nature and tenacity in seeking to uncover information on her lost husband and his crew. Some other themes are the trust (well placed, as it turned out) that she accorded Captain M'Clintock and the distinct favour or disfavour with which she viewed various other Arctic personalities of the era. These themes have been commented upon in the past, but are confirmed by the documents. This article summarizes the content of the documents, places them in historical context, and quotes the two most significant letters in their entirety.On vient de découvrir un dossier de documents contemporains ayant trait à l'expédition Fox qui fut lancée à la recherche de sir John Franklin. Il contient 14 lettres personnelles adressées au capitaine F. L. M'Clintock par lady Jane Franklin et sa nièce, Sophia Cracroft; des coupures de journaux contenant de longues lettres écrites par l'explorateur John Rae et par Allen Young, troisième officier à bord du Fox; et un dessin. À une exception près, c'est la première fois que ces documents font l'objet d'une étude de la part de spécialistes. Un élément inédit est l'offre de commandement du Fox faite par lady Jane Franklin au capitaine F. L. M'Clintock. Les documents, qui sont maintenant entre les mains de l'auteur, affirment le caractère énergique et la ténacité de lady Franklin à vouloir découvrir ce qu'il était advenu de son mari et de l'équipage disparus. D'autres thèmes qui ressortent sont la confiance (bien placée, comme le confirmeront les événements) qu'elle accorda au capitaine M'Clintock et sa façon très nette de considérer d'un bon ou d'un mauvais œil les divers personnages de l'époque ayant affaire avec l'Arctique. Ces thèmes, qui ont déjà fait l'objet de commentaires dans le passé, sont confirmés par les documents. L'article résume le contenu de ces derniers, les replace dans un contexte historique et cite les deux lettres les plus importantes dans leur intégralité

Cloud detection by lidar extinction calculations

A new lidar method of measuring cloud ceiling height using the Klett solution to the lidar equation was developed. This simple technique will find cloud ceiling height for clouds that rangefinder-like lidars cannot theoretically detect. In addition, the noise signals that do not correspond to clouds removed by using the convergence of the Klett solution to discriminate between signal changes and broader signal changes due to clouds. Clouds above rain or light fog can be detected without error, and it is possible to discriminate against haze layers by the magnitude of their maximum extinction

A Proposal to Detect Dark Matter Using Axionic Topological Antiferromagnets

Antiferromagnetically doped topological insulators (A-TI) are among the candidates to host dynamical axion fields and axion-polaritons; weakly interacting quasiparticles that are analogous to the dark axion, a long sought after candidate dark matter particle. Here we demonstrate that using the axion quasiparticle antiferromagnetic resonance in A-TI's in conjunction with low-noise methods of detecting THz photons presents a viable route to detect axion dark matter with mass 0.7 to 3.5 meV, a range currently inaccessible to other dark matter detection experiments and proposals. The benefits of this method at high frequency are the tunability of the resonance with applied magnetic field, and the use of A-TI samples with volumes much larger than 1 mm$^3$.Comment: 6 pages, 4 figures. v2 accepted for publication in Physical Review Letters. Many points clarified, some parameter estimates revise