d-calibers and d-tightness in compact spaces

We study the Čech–Stone compactification of the space Seq ( u ) . We show that its remainder is F σ κ -closed whenever u is a P ( κ ) -point and b ⩾ κ > ω . Our results enable us to solve a recent problem by Okunev and Tkachuk regarding a possible relationship between d-tightness and d-calibers in compact spaces.